diff --git a/config/platforms/platform_cygwin.h.in b/config/platforms/platform_cygwin.h.in
index cfe458b58b..3144e060b4 100644
--- a/config/platforms/platform_cygwin.h.in
+++ b/config/platforms/platform_cygwin.h.in
@@ -12,4 +12,4 @@
 #define DUK_SETJMP(jb)        _setjmp((jb))
 #define DUK_LONGJMP(jb)       _longjmp((jb), 1)
 
-#define DUK_USE_OS_STRING "windows"
+#define DUK_USE_OS_STRING "cygwin"