Com`ple*men"tal (?), a. 1. Supplying, or tending to supply, a deficiency; fully completing. "Complemental ceremony." Prynne.

2. Complimentary; courteous. [Obs.] Shak.

Complemental air(Physiol.), the air (averaging 100 cubic inches) which can be drawn into the lungs in addition to the tidal air, by the deepest possible inspiration. -- Complemental males(Zoöl.), peculiar small males living parasitically on the ordinary hermaphrodite individuals of certain barnacles.