vitellus Meaning, Definition & Usage

  1. noun nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg)
    yolk.

WordNet

Vi*tel"lus noun
Etymology
L., the yolk of an egg.
Definitions
  1. (Biol.) The contents or substance of the ovum; egg yolk. See Illust. of Ovum.
  2. (Bot.) Perisperm in an early condition.

Webster 1913