Entom. [mod L.; see SUB- 1 f.] The basal part of the labium.
1877. Huxley, Anat. Inv. Anim., vii. 403. The submentum is not directly articulated with the cranial skeleton.
1888. Rolleston & Jackson, Anim. Life, 141. The labium consists (1) of a large basal sub-mentum (2) a mentum; (3) of two three-jointed palpi (4) a ligula.