diff --git a/src/collocatordb.h b/src/collocatordb.h
index 0eed8d8..d601902 100644
--- a/src/collocatordb.h
+++ b/src/collocatordb.h
@@ -128,4 +128,6 @@
 extern char *get_word(COLLOCATORDB *db, uint32_t w1);
 extern void read_vocab(COLLOCATORDB *db, char *fname);
 extern char *get_version();
+extern uint64_t get_word_id(COLLOCATORDB *db, const char *word);
+
 #endif