Meaning of definiendum

de•fin•i•en•dum

Pronunciation: (di-fin"ē-en'dum), [key]
— pl. -da
  1. something that is or is to be defined, esp. the term at the head of a dictionary entry.
  2. an expression to be defined in terms of another expression previously defined. Cf. definiens.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.