dertrum: Meaning and Definition of

der•trum

Pronunciation: (dûr'trum), [key]
— pl. -tra
  1. the extremity of the maxilla of a bird's bill, esp. when hooked or differentiated from the rest of the bill, as in pigeons and plovers.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.