complemental

from WordNet (r) 3.0 (2006)

complemental
    adj 1: acting as or providing a complement (something that
           completes the whole) [syn: {complemental},
           {complementary}, {completing}]

from The Collaborative International Dictionary of English v.0.48

Complemental \Com`ple*men"tal\, a.
   1. Supplying, or tending to supply, a deficiency; fully
      completing. "Complemental ceremony." --Prynne.
      [1913 Webster]

   2. Complimentary; courteous. [Obs.] --Shak.
      [1913 Webster]

   {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} (Zool.), peculiar small males living
      parasitically on the ordinary hermaphrodite individuals of
      certain barnacles.
      [1913 Webster]