patch 7.4.1799
Problem:    'guicolors' is a confusing option name.
Solution:   Use 'termguicolors' instead. (Hirohito Higashi)
diff --git a/src/feature.h b/src/feature.h
index d3d768e..54f665f 100644
--- a/src/feature.h
+++ b/src/feature.h
@@ -815,10 +815,10 @@
 #endif
 
 /*
- * +termtruecolor	'guicolor' option.
+ * +termguicolors	'termguicolors' option.
  */
 #if (defined(FEAT_BIG) && defined(FEAT_SYN_HL)) && !defined(ALWAYS_USE_GUI)
-# define FEAT_TERMTRUECOLOR
+# define FEAT_TERMGUICOLORS
 #endif
 
 /* Mac specific thing: Codewarrior interface. */