diff --git a/src/ncp/spinel.h b/src/ncp/spinel.h
index 5b0757e11..001a4f80c 100644
--- a/src/ncp/spinel.h
+++ b/src/ncp/spinel.h
@@ -658,7 +658,6 @@ typedef struct
 typedef int          spinel_ssize_t;
 typedef unsigned int spinel_size_t;
 typedef uint8_t      spinel_tid_t;
-typedef unsigned int spinel_cid_t;
 
 enum
 {