Labellum -a: the sensitive ridged tip of the mouth structures of certain Diptera: a prolongation of the labium covering the base of rostrum in Coleoptera and Hemiptera.
Labial: referring, pertaining or belonging to the labium.
Labial segment: the 7th segment of head = second maxillary segment.
Labial suture: is between labium and mentum.
Labiate: lip-like or having lip-like sutures.
Labipalp: a labial palpus.
Labis: the slender abdominal forceps in some Lepidoptera.
Labium: the lower lip: a compound structure which forms the floor of the mouth in mandibulate insects, behind the first maxilla and opposed to the labium; formed by a fusion in embryonic life of separate right and left maxilla-like halves: in some of its developments referred to as the tongue.
Labral suture: is between labrum and clypeus.