diff --git a/src/libespeak-ng/dictionary.c b/src/libespeak-ng/dictionary.c
index 255ed4db..5d519981 100644
--- a/src/libespeak-ng/dictionary.c
+++ b/src/libespeak-ng/dictionary.c
@@ -43,6 +43,8 @@
 #include "synthesize.h"                    // for STRESS_IS_PRIMARY, phoneme...
 #include "translate.h"                     // for Translator, utf8_in, LANGU...
 
+static int LookupFlags(Translator *tr, const char *word, unsigned int **flags_out);
+
 typedef struct {
 	int points;
 	const char *phonemes;
@@ -2904,7 +2906,7 @@ int Lookup(Translator *tr, const char *word, char *ph_out)
 	return flags0;
 }
 
-int LookupFlags(Translator *tr, const char *word, unsigned int **flags_out)
+static int LookupFlags(Translator *tr, const char *word, unsigned int **flags_out)
 {
 	char buf[100];
 	static unsigned int flags[2];
diff --git a/src/libespeak-ng/dictionary.h b/src/libespeak-ng/dictionary.h
index e09492e1..5b9890d4 100644
--- a/src/libespeak-ng/dictionary.h
+++ b/src/libespeak-ng/dictionary.h
@@ -47,7 +47,6 @@ int TranslateRules(Translator *tr, char *p_start, char *phonemes, int ph_size, c
 int TransposeAlphabet(Translator *tr, char *text);
 int Lookup(Translator *tr, const char *word, char *ph_out);
 int LookupDictList(Translator *tr, char **wordptr, char *ph_out, unsigned int *flags, int end_flags, WORD_TAB *wtab);
-int LookupFlags(Translator *tr, const char *word, unsigned int **flags_out);
 int RemoveEnding(Translator *tr, char *word, int end_type, char *word_copy);
 
 #ifdef __cplusplus