diff --git a/basis/compiler/cfg/instructions/instructions.factor b/basis/compiler/cfg/instructions/instructions.factor
index 210489f8b0..29d9f4a5fd 100644
--- a/basis/compiler/cfg/instructions/instructions.factor
+++ b/basis/compiler/cfg/instructions/instructions.factor
@@ -608,7 +608,7 @@ literal: offset rep c-type ;
 ! Memory allocation
 FLUSHABLE-INSN: ##allot
 def: dst/tagged-rep
-literal: size class
+literal: size class-of
 temp: temp/int-rep ;
 
 VREG-INSN: ##write-barrier
diff --git a/basis/compiler/cfg/intrinsics/simd/simd-tests.factor b/basis/compiler/cfg/intrinsics/simd/simd-tests.factor
index 96c8da8ace..6d0deff5b3 100644
--- a/basis/compiler/cfg/intrinsics/simd/simd-tests.factor
+++ b/basis/compiler/cfg/intrinsics/simd/simd-tests.factor
@@ -22,7 +22,7 @@ IN: compiler.cfg.intrinsics.simd.tests
     } ;
 
 :: test-node-literal ( lit rep -- node )
-    lit class :> lit-class
+    lit class-of :> lit-class
     T{ #call
         { in-d  { 1 2 3 4 } }
         { out-d { 5 } }
@@ -63,7 +63,7 @@ IN: compiler.cfg.intrinsics.simd.tests
         H{ } clone \ kill-sets pick set-at ;
 
 : make-classes ( quot -- seq )
-    { } make [ class ] map ; inline
+    { } make [ class-of ] map ; inline
 
 : test-emit ( cpu rep quot -- node )
     [
diff --git a/basis/compiler/tests/alien.factor b/basis/compiler/tests/alien.factor
index feb18e0d7a..ff11ac7eb9 100755
--- a/basis/compiler/tests/alien.factor
+++ b/basis/compiler/tests/alien.factor
@@ -466,7 +466,7 @@ STRUCT: double-rect
 [
     1.0 2.0 3.0 4.0 <double-rect>
     double-rect-callback double-rect-test
-    [ >c-ptr class ] [ >double-rect< ] bi
+    [ >c-ptr class-of ] [ >double-rect< ] bi
 ] unit-test
 
 STRUCT: test_struct_14
diff --git a/basis/compiler/tests/intrinsics.factor b/basis/compiler/tests/intrinsics.factor
index 00345081ca..2ca0270c79 100644
--- a/basis/compiler/tests/intrinsics.factor
+++ b/basis/compiler/tests/intrinsics.factor
@@ -325,7 +325,7 @@ ERROR: bug-in-fixnum* x y a b ;
 
 : compiled-fixnum>bignum ( a -- b ) fixnum>bignum ;
 
-[ bignum ] [ 0 compiled-fixnum>bignum class ] unit-test
+[ bignum ] [ 0 compiled-fixnum>bignum class-of ] unit-test
 
 [ ] [
     10000 [
diff --git a/basis/compiler/tests/optimizer.factor b/basis/compiler/tests/optimizer.factor
index ac86519919..84a75c44eb 100644
--- a/basis/compiler/tests/optimizer.factor
+++ b/basis/compiler/tests/optimizer.factor
@@ -431,7 +431,7 @@ M: object bad-dispatch-position-test* ;
 [ -1 ] [ 3 4 0 dispatch-branch-problem ] unit-test
 [ 12 ] [ 3 4 1 dispatch-branch-problem ] unit-test
 
-[ 1024 bignum ] [ 10 [ 1 >bignum swap >fixnum shift ] compile-call dup class ] unit-test
+[ 1024 bignum ] [ 10 [ 1 >bignum swap >fixnum shift ] compile-call dup class-of ] unit-test
 
 TUPLE: grid-mesh-tuple { length read-only } { step read-only } ;
 
diff --git a/basis/compiler/tree/def-use/simplified/simplified-tests.factor b/basis/compiler/tree/def-use/simplified/simplified-tests.factor
index 72c7e4c60c..ccc4ef02cd 100644
--- a/basis/compiler/tree/def-use/simplified/simplified-tests.factor
+++ b/basis/compiler/tree/def-use/simplified/simplified-tests.factor
@@ -6,7 +6,7 @@ IN: compiler.tree.def-use.simplified
 [ { #call #return } ] [
     [ 1 dup reverse ] build-tree compute-def-use
     first out-d>> first actually-used-by
-    [ node>> class ] map natural-sort
+    [ node>> class-of ] map natural-sort
 ] unit-test
 
 : word-1 ( a -- b ) dup [ word-1 ] when ; inline recursive
@@ -14,11 +14,11 @@ IN: compiler.tree.def-use.simplified
 [ { #introduce } ] [
     [ word-1 ] build-tree analyze-recursive compute-def-use
     last in-d>> first actually-defined-by
-    [ node>> class ] map natural-sort
+    [ node>> class-of ] map natural-sort
 ] unit-test
 
 [ { #if #return } ] [
     [ word-1 ] build-tree analyze-recursive compute-def-use
     first out-d>> first actually-used-by
-    [ node>> class ] map natural-sort
-] unit-test
\ No newline at end of file
+    [ node>> class-of ] map natural-sort
+] unit-test
diff --git a/basis/compiler/tree/escape-analysis/escape-analysis-tests.factor b/basis/compiler/tree/escape-analysis/escape-analysis-tests.factor
index ca2f5ed197..ff67059e1e 100644
--- a/basis/compiler/tree/escape-analysis/escape-analysis-tests.factor
+++ b/basis/compiler/tree/escape-analysis/escape-analysis-tests.factor
@@ -21,7 +21,7 @@ M: #call count-unboxed-allocations*
     [ (count-unboxed-allocations) ] [ drop ] if ;
 
 M: #push count-unboxed-allocations*
-    dup literal>> class immutable-tuple-class?
+    dup literal>> class-of immutable-tuple-class?
     [ (count-unboxed-allocations) ] [ drop ] if ;
 
 M: #introduce count-unboxed-allocations*
diff --git a/basis/db/tuples/tuples-tests.factor b/basis/db/tuples/tuples-tests.factor
index 7f109d80e0..90131068d2 100644
--- a/basis/db/tuples/tuples-tests.factor
+++ b/basis/db/tuples/tuples-tests.factor
@@ -523,12 +523,12 @@ TUPLE: does-not-persist ;
 
 [
     [ does-not-persist create-sql-statement ]
-    [ class \ not-persistent = ] must-fail-with
+    [ class-of \ not-persistent = ] must-fail-with
 ] test-sqlite
 
 [
     [ does-not-persist create-sql-statement ]
-    [ class \ not-persistent = ] must-fail-with
+    [ class-of \ not-persistent = ] must-fail-with
 ] test-postgresql
 
 
diff --git a/basis/dlists/dlists-tests.factor b/basis/dlists/dlists-tests.factor
index ab27304350..1ca7c0771a 100644
--- a/basis/dlists/dlists-tests.factor
+++ b/basis/dlists/dlists-tests.factor
@@ -53,9 +53,9 @@ IN: dlists.tests
 [ t ] [ <dlist> 1 over push-back dup [ 1 = ] delete-node-if drop deque-empty? ] unit-test
 [ t ] [ <dlist> 1 over push-back dup [ 1 = ] delete-node-if drop deque-empty? ] unit-test
 
-[ t ] [ <dlist> 4 over push-back 5 over push-back [ obj>> 4 = ] dlist-find-node class dlist-node = ] unit-test
-[ t ] [ <dlist> 4 over push-back 5 over push-back [ obj>> 5 = ] dlist-find-node class dlist-node = ] unit-test
-[ t ] [ <dlist> 4 over push-back 5 over push-back* [ = ] curry dlist-find-node class dlist-node = ] unit-test
+[ t ] [ <dlist> 4 over push-back 5 over push-back [ obj>> 4 = ] dlist-find-node class-of dlist-node = ] unit-test
+[ t ] [ <dlist> 4 over push-back 5 over push-back [ obj>> 5 = ] dlist-find-node class-of dlist-node = ] unit-test
+[ t ] [ <dlist> 4 over push-back 5 over push-back* [ = ] curry dlist-find-node class-of dlist-node = ] unit-test
 [ ] [ <dlist> 4 over push-back 5 over push-back [ drop ] dlist-each ] unit-test
 
 [ <dlist> peek-front ] [ empty-dlist? ] must-fail-with
diff --git a/basis/help/syntax/syntax-tests.factor b/basis/help/syntax/syntax-tests.factor
index 7618e9cdeb..cc278a162a 100644
--- a/basis/help/syntax/syntax-tests.factor
+++ b/basis/help/syntax/syntax-tests.factor
@@ -5,13 +5,13 @@ IN: help.syntax.tests
 [
     [ "foobar" ] [
         "IN: help.syntax.tests USE: help.syntax ABOUT: \"foobar\"" eval( -- )
-        "help.syntax.tests" vocab vocab-help
+        "help.syntax.tests" lookup-vocab vocab-help
     ] unit-test
     
     [ { "foobar" } ] [
         "IN: help.syntax.tests USE: help.syntax ABOUT: { \"foobar\" }" eval( -- )
-        "help.syntax.tests" vocab vocab-help
+        "help.syntax.tests" lookup-vocab vocab-help
     ] unit-test
     
-    [ ] [ "help.syntax.tests" vocab f >>help drop ] unit-test
+    [ ] [ "help.syntax.tests" lookup-vocab f >>help drop ] unit-test
 ] with-file-vocabs
diff --git a/basis/help/vocabs/vocabs-tests.factor b/basis/help/vocabs/vocabs-tests.factor
index aca1ae43c9..bb7096824b 100644
--- a/basis/help/vocabs/vocabs-tests.factor
+++ b/basis/help/vocabs/vocabs-tests.factor
@@ -2,5 +2,5 @@ USING: help.vocabs tools.test help.markup help vocabs io ;
 IN: help.vocabs.tests
 
 [ ] [ { $vocab "scratchpad" } print-content ] unit-test
-[ ] [ "classes" vocab print-topic ] unit-test
+[ ] [ "classes" lookup-vocab print-topic ] unit-test
 [ ] [ nl ] unit-test
diff --git a/basis/io/sockets/secure/unix/unix-tests.factor b/basis/io/sockets/secure/unix/unix-tests.factor
index 3572a9a845..551e0c65ad 100644
--- a/basis/io/sockets/secure/unix/unix-tests.factor
+++ b/basis/io/sockets/secure/unix/unix-tests.factor
@@ -26,7 +26,7 @@ io.sockets.secure.unix.debug ;
         "127.0.0.1" "port" get ?promise <inet4> <secure> ascii <client> drop stream-contents
     ] with-secure-context ;
 
-[ ] [ [ class name>> write ] server-test ] unit-test
+[ ] [ [ class-of name>> write ] server-test ] unit-test
 
 [ "secure" ] [ client-test ] unit-test
 
diff --git a/basis/math/intervals/intervals-tests.factor b/basis/math/intervals/intervals-tests.factor
index 3fa3e97cba..b9e09264d9 100644
--- a/basis/math/intervals/intervals-tests.factor
+++ b/basis/math/intervals/intervals-tests.factor
@@ -153,7 +153,7 @@ IN: math.intervals.tests
 
 [ t ] [ -1 1 (a,b) 0 1 (a,b) interval/ [-inf,inf] = ] unit-test
 
-"math.ratios.private" vocab [
+"math.ratios.private" lookup-vocab [
     [ t ] [
         -1 1 (a,b) 0.5 1 (a,b) interval/ -2.0 2.0 (a,b) =
     ] unit-test
@@ -277,7 +277,7 @@ IN: math.intervals.tests
         { 2/ interval-2/ }
         { neg interval-neg }
     }
-    "math.ratios.private" vocab [
+    "math.ratios.private" lookup-vocab [
         { recip interval-recip } suffix
     ] when ;
 
@@ -308,7 +308,7 @@ unary-ops [
         { min interval-min }
         { max interval-max }
     }
-    "math.ratios.private" vocab [
+    "math.ratios.private" lookup-vocab [
         { / interval/ } suffix
     ] when ;
 
diff --git a/basis/math/vectors/simd/simd-tests.factor b/basis/math/vectors/simd/simd-tests.factor
index 3b9e4ffc67..264dbbce59 100644
--- a/basis/math/vectors/simd/simd-tests.factor
+++ b/basis/math/vectors/simd/simd-tests.factor
@@ -127,7 +127,7 @@ CONSTANT: vector-words
 : check-optimizer ( seq quot eq-quot -- failures )
     dup '[
         @
-        [ dup [ class ] { } map-as ] dip '[ _ declare @ ]
+        [ dup [ class-of ] { } map-as ] dip '[ _ declare @ ]
         {
             [ "print-mr" get [ nip regs. ] [ 2drop ] if ]
             [ "print-checks" get [ [ . ] bi@ ] [ 2drop ] if ]
diff --git a/basis/present/present-tests.factor b/basis/present/present-tests.factor
index 022ae9d6d9..2208ee4fdd 100644
--- a/basis/present/present-tests.factor
+++ b/basis/present/present-tests.factor
@@ -4,5 +4,5 @@ USING: tools.test vocabs.hierarchy present math vocabs sequences kernel ;
 [ "3" ] [ 3 present ] unit-test
 [ "Hi" ] [ "Hi" present ] unit-test
 [ "+" ] [ \ + present ] unit-test
-[ "kernel" ] [ "kernel" vocab present ] unit-test
+[ "kernel" ] [ "kernel" lookup-vocab present ] unit-test
 [ ] [ all-vocabs-recursive filter-vocabs [ present ] map drop ] unit-test
diff --git a/basis/serialize/serialize-tests.factor b/basis/serialize/serialize-tests.factor
index 639cc1e2b0..2bfd99f113 100644
--- a/basis/serialize/serialize-tests.factor
+++ b/basis/serialize/serialize-tests.factor
@@ -59,7 +59,7 @@ CONSTANT: objects
 
 : check-serialize-1 ( obj -- ? )
     "=====" print
-    dup class .
+    dup class-of .
     dup .
     dup
     object>bytes
@@ -71,7 +71,7 @@ CONSTANT: objects
         drop t ! we don't care if numbers aren't interned
     ] [
         "=====" print
-        dup class .
+        dup class-of .
         dup 2array dup .
         object>bytes
         bytes>object dup .
diff --git a/basis/ui/gadgets/grids/grids-tests.factor b/basis/ui/gadgets/grids/grids-tests.factor
index 3dc0e6b862..5775e55fe7 100644
--- a/basis/ui/gadgets/grids/grids-tests.factor
+++ b/basis/ui/gadgets/grids/grids-tests.factor
@@ -98,7 +98,7 @@ IN: ui.gadgets.grids.tests
 [ { 0 250 } ] [ "b" get loc>> ] unit-test
 
 [ gadget { 200 200 } ]
-[ { 120 20 } "g" get pick-up [ class ] [ dim>> ] bi ] unit-test
+[ { 120 20 } "g" get pick-up [ class-of ] [ dim>> ] bi ] unit-test
 
 [ gadget { 200 200 } ]
-[ { 120 220 } "g" get pick-up [ class ] [ dim>> ] bi ] unit-test
\ No newline at end of file
+[ { 120 220 } "g" get pick-up [ class-of ] [ dim>> ] bi ] unit-test
diff --git a/basis/xml/syntax/syntax-tests.factor b/basis/xml/syntax/syntax-tests.factor
index 40c86237a7..c30feab039 100644
--- a/basis/xml/syntax/syntax-tests.factor
+++ b/basis/xml/syntax/syntax-tests.factor
@@ -90,10 +90,10 @@ XML-NS: foo http://blah.com
 [ [XML <-> XML] ] must-infer
 [ [XML <foo><-></foo> <bar val=<->/> XML] ] must-infer
 
-[ xml-chunk ] [ [ [XML <foo/> XML] ] first class ] unit-test
-[ xml ] [ [ <XML <foo/> XML> ] first class ] unit-test
-[ xml-chunk ] [ [ [XML <foo val=<->/> XML] ] third class ] unit-test
-[ xml ] [ [ <XML <foo val=<->/> XML> ] third class ] unit-test
+[ xml-chunk ] [ [ [XML <foo/> XML] ] first class-of ] unit-test
+[ xml ] [ [ <XML <foo/> XML> ] first class-of ] unit-test
+[ xml-chunk ] [ [ [XML <foo val=<->/> XML] ] third class-of ] unit-test
+[ xml ] [ [ <XML <foo val=<->/> XML> ] third class-of ] unit-test
 [ 1 ] [ [ [XML <foo/> XML] ] length ] unit-test
 [ 1 ] [ [ <XML <foo/> XML> ] length ] unit-test
 
diff --git a/core/growable/growable-tests.factor b/core/growable/growable-tests.factor
index 7ba67fe97b..584d6a1918 100644
--- a/core/growable/growable-tests.factor
+++ b/core/growable/growable-tests.factor
@@ -4,7 +4,7 @@ IN: growable.tests
 
 ! erg found this one
 [ fixnum ] [
-    2 >bignum V{ } [ set-length ] keep length class
+    2 >bignum V{ } [ set-length ] keep length class-of
 ] unit-test
 
 ! overflow bugs
diff --git a/core/io/binary/binary-tests.factor b/core/io/binary/binary-tests.factor
index 3556e66631..fc94c1a7ff 100644
--- a/core/io/binary/binary-tests.factor
+++ b/core/io/binary/binary-tests.factor
@@ -24,7 +24,7 @@ IN: io.binary.tests
 [ 1234 ] [ 1234 4 >be be> ] unit-test
 [ 1234 ] [ 1234 4 >le le> ] unit-test
 
-[ fixnum ] [ B{ 0 0 0 0 0 0 0 0 0 0 } be> class ] unit-test
+[ fixnum ] [ B{ 0 0 0 0 0 0 0 0 0 0 } be> class-of ] unit-test
 
 [ HEX: 56780000 HEX: 12340000 ] [ HEX: 1234000056780000 d>w/w ] unit-test
 [ HEX: 5678 HEX: 1234 ] [ HEX: 12345678 w>h/h ] unit-test
diff --git a/core/parser/parser-tests.factor b/core/parser/parser-tests.factor
index b0943995c2..b5530e32b6 100644
--- a/core/parser/parser-tests.factor
+++ b/core/parser/parser-tests.factor
@@ -46,7 +46,7 @@ unit-test
 ! Test EOL comments in multiline strings.
 [ "Hello" ] [ "#! This calls until-eol.\n\"Hello\"" eval( -- string ) ] unit-test
 
-[ word ] [ \ f class ] unit-test
+[ word ] [ \ f class-of ] unit-test
 
 ! Test stack effect parsing
 
diff --git a/core/sbufs/sbufs-tests.factor b/core/sbufs/sbufs-tests.factor
index 6711870f74..9c2bcaeb6e 100644
--- a/core/sbufs/sbufs-tests.factor
+++ b/core/sbufs/sbufs-tests.factor
@@ -19,6 +19,6 @@ IN: sbufs.tests
 
 [ SBUF" x" ] [ 1 <sbuf> CHAR: x >bignum over push ] unit-test
 
-[ fixnum ] [ 1 >bignum SBUF" " new-sequence length class ] unit-test
+[ fixnum ] [ 1 >bignum SBUF" " new-sequence length class-of ] unit-test
 
-[ fixnum ] [ 1 >bignum iota [ ] SBUF" " map-as length class ] unit-test
+[ fixnum ] [ 1 >bignum iota [ ] SBUF" " map-as length class-of ] unit-test
diff --git a/core/vectors/vectors-tests.factor b/core/vectors/vectors-tests.factor
index 8f644963bf..8e6b13d9ab 100644
--- a/core/vectors/vectors-tests.factor
+++ b/core/vectors/vectors-tests.factor
@@ -94,8 +94,8 @@ IN: vectors.tests
     100 iota >array dup >vector <reversed> >array [ reverse ] dip =
 ] unit-test
 
-[ fixnum ] [ 1 >bignum V{ } new-sequence length class ] unit-test
+[ fixnum ] [ 1 >bignum V{ } new-sequence length class-of ] unit-test
 
-[ fixnum ] [ 1 >bignum iota [ ] V{ } map-as length class ] unit-test
+[ fixnum ] [ 1 >bignum iota [ ] V{ } map-as length class-of ] unit-test
 
 [ V{ "lulz" } ] [ "lulz" 1vector ] unit-test
diff --git a/extra/irc/client/internals/internals-tests.factor b/extra/irc/client/internals/internals-tests.factor
index 377c80cf51..be1e94cd70 100644
--- a/extra/irc/client/internals/internals-tests.factor
+++ b/extra/irc/client/internals/internals-tests.factor
@@ -67,7 +67,7 @@ M: mb-writer dispose drop ;
 
 { privmsg "#channel" "hello" } [
     "#channel" "hello" strings>privmsg
-    [ class ] [ target>> ] [ trailing>> ] tri
+    [ class-of ] [ target>> ] [ trailing>> ] tri
 ] unit-test
 
 ! Test login and nickname set
@@ -121,7 +121,7 @@ M: mb-writer dispose drop ;
         ":ircserver.net 477 factorbot #factortest :[ircserver-info] blah blah"
       } %push-lines
       [ join? ] read-matching-message
-      [ class ] [ channel>> ] bi
+      [ class-of ] [ channel>> ] bi
   ] unit-test
 ] spawning-irc
 
@@ -129,7 +129,7 @@ M: mb-writer dispose drop ;
       "#factortest" <irc-channel-chat> [ %add-named-chat ] keep
       ":somebody!n=somebody@some.where PRIVMSG #factortest :hello" %push-line
       [ privmsg? ] read-matching-message
-      [ class ] [ target>> ] [ trailing>> ] tri
+      [ class-of ] [ target>> ] [ trailing>> ] tri
   ] unit-test
 ] spawning-irc
 
@@ -137,7 +137,7 @@ M: mb-writer dispose drop ;
       "ircuser" <irc-nick-chat>  [ %add-named-chat ] keep
       ":ircuser!n=user@isp.net PRIVMSG factorbot :hello" %push-line
       [ privmsg? ] read-matching-message
-      [ class ] [ target>> ] [ trailing>> ] tri
+      [ class-of ] [ target>> ] [ trailing>> ] tri
   ] unit-test
 ] spawning-irc
 
@@ -145,7 +145,7 @@ M: mb-writer dispose drop ;
       "#factortest" <irc-channel-chat>  [ %add-named-chat ] keep
       ":ircserver.net MODE #factortest +ns" %push-line
       [ mode? ] read-matching-message
-      [ class ] [ name>> ] [ mode>> ] tri
+      [ class-of ] [ name>> ] [ mode>> ] tri
   ] unit-test
 ] spawning-irc
 
@@ -215,7 +215,7 @@ M: mb-writer dispose drop ;
       "ircuser" over join-participant
       ":ircserver.net MODE #factortest +o ircuser" %push-line
       [ mode? ] read-matching-message
-      { [ class ] [ name>> ] [ mode>> ] [ parameter>> ] } cleave
+      { [ class-of ] [ name>> ] [ mode>> ] [ parameter>> ] } cleave
   ] unit-test
 ] spawning-irc
 
diff --git a/extra/multi-methods/tests/syntax.factor b/extra/multi-methods/tests/syntax.factor
index afe6037adc..1de8503b29 100644
--- a/extra/multi-methods/tests/syntax.factor
+++ b/extra/multi-methods/tests/syntax.factor
@@ -38,7 +38,7 @@ SYMBOL: some-var
 multi-methods:GENERIC: hook-test ( obj -- obj )
 
 METHOD: hook-test { array { some-var array } } reverse ;
-METHOD: hook-test { { some-var array } } class ;
+METHOD: hook-test { { some-var array } } class-of ;
 METHOD: hook-test { hashtable { some-var number } } assoc-size ;
 
 { 1 2 3 } some-var set
diff --git a/extra/pair-methods/pair-methods-tests.factor b/extra/pair-methods/pair-methods-tests.factor
index f88ca966aa..ba8d5df4f0 100644
--- a/extra/pair-methods/pair-methods-tests.factor
+++ b/extra/pair-methods/pair-methods-tests.factor
@@ -11,7 +11,7 @@ TUPLE: zim < thang ;
 TUPLE: zang < zim ;
 
 : class-names ( a b prefix -- string )
-    [ [ class name>> ] bi@ "-" glue ] dip prepend ;
+    [ [ class-of name>> ] bi@ "-" glue ] dip prepend ;
 
 PAIR-GENERIC: blibble ( a b -- c )
 
diff --git a/extra/pair-methods/pair-methods.factor b/extra/pair-methods/pair-methods.factor
index 2ebb110c24..3d4e6a8fb1 100644
--- a/extra/pair-methods/pair-methods.factor
+++ b/extra/pair-methods/pair-methods.factor
@@ -26,7 +26,7 @@ ERROR: no-pair-method a b generic ;
 : pair-generic-definition ( word -- def )
     [ sorted-pair-methods [ first2 pair-method-cond ] map ]
     [ [ no-pair-method ] curry suffix ] bi 1quotation
-    [ 2dup [ class ] compare +gt+ eq? ?swap ] [ cond ] surround ;
+    [ 2dup [ class-of ] compare +gt+ eq? ?swap ] [ cond ] surround ;
 
 : make-pair-generic ( word -- )
     dup pair-generic-definition define ;