diff --git a/native/jni/src/defines.h b/native/jni/src/defines.h
index fdfe4ec..9b53007 100644
--- a/native/jni/src/defines.h
+++ b/native/jni/src/defines.h
@@ -211,8 +211,7 @@
 
 #define DICTIONARY_VERSION_MIN 200
 #define NOT_VALID_WORD -99
-// TODO: NOT_A_CHARACTER should be -1
-#define NOT_A_CHARACTER 0xFFFF // tentative
+#define NOT_A_CHARACTER -1
 #define NOT_A_DISTANCE -1
 #define NOT_A_COORDINATE -1
 #define EQUIVALENT_CHAR_WITHOUT_DISTANCE_INFO -2