diff --git a/extra/math/floating-point/floating-point-tests.factor b/extra/math/floating-point/floating-point-tests.factor
index 129956331b..9e5b5c67aa 100644
--- a/extra/math/floating-point/floating-point-tests.factor
+++ b/extra/math/floating-point/floating-point-tests.factor
@@ -13,5 +13,3 @@ IN: math.floating-point.tests
 [ f ] [ 10. infinity? ] unit-test
 [ f ] [ -10. infinity? ] unit-test
 [ f ] [ 0. infinity? ] unit-test
-
-[ t ] [ 0/0. nan? ] unit-test
diff --git a/extra/math/floating-point/floating-point.factor b/extra/math/floating-point/floating-point.factor
index 02fcd01e11..522f149bc1 100644
--- a/extra/math/floating-point/floating-point.factor
+++ b/extra/math/floating-point/floating-point.factor
@@ -38,13 +38,6 @@ IN: math.floating-point
         11 [ bl ] times print
     ] tri ;
 
-: nan? ( double -- ? )
-    double>bits
-    {
-        [ (double-exponent-bits) 11 on-bits = ]
-        [ (double-mantissa-bits) 0 > ]
-    } 1&& ;
-
 : infinity? ( double -- ? )
     double>bits
     {