yolk Meaning, Definition & Usage

  1. noun the yellow spherical part of an egg that is surrounded by the albumen
    egg yolk.
  2. noun nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg)
    vitellus.

WordNet

Yolk noun
Etymology
OE. yolke, yelke, ýolke, ýelke, AS. geoloca, geoleca, fr. geolu yellow. See Yellow.
Definitions
  1. The yellow part of an egg; the vitellus.
  2. (Zoöl.) An oily secretion which naturally covers the wool of sheep.

Webster 1913