diff --git a/sys/net80211/ieee80211_radiotap.h b/sys/net80211/ieee80211_radiotap.h
index 9cac685fda9..c474e32ccfb 100644
--- a/sys/net80211/ieee80211_radiotap.h
+++ b/sys/net80211/ieee80211_radiotap.h
@@ -212,5 +212,6 @@ enum ieee80211_radiotap_type {
 						 * 802.11 header and payload
 						 * (to 32-bit boundary)
 						 */
+#define	IEEE80211_RADIOTAP_F_BADFCS	0x40	/* does not pass FCS check */
 
 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */