Yolk sack
Yolk Yolk (y[=o]lk or y[=o]k; 277), n. [OE. yolke, yelke, [yogh]olke, [yogh]elke, AS. geoloca, geoleca, fr. geolu yellow. See {Yellow}.] [Written also {yelk}.] [1913 Webster] 1. The yellow part of an egg; the vitellus. [1913 Webster]

2. (Zo["o]l.) An oily secretion which naturally covers the wool of sheep. [1913 Webster]

{Yolk cord} (Zo["o]l.), a slender cord or duct which connects the yolk glands with the egg chambers in certain insects, as in the aphids.

{Yolk gland} (Zo["o]l.), a special organ which secretes the yolk of the eggs in many turbellarians, and in some other invertebrates. See Illust. of {Hermaphrodite} in Appendix.

{Yolk sack} (Anat.), the umbilical vesicle. See under {Unbilical}. [1913 Webster]


The Collaborative International Dictionary of English. 2000.

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  • Yolk — (y[=o]lk or y[=o]k; 277), n. [OE. yolke, yelke, [yogh]olke, [yogh]elke, AS. geoloca, geoleca, fr. geolu yellow. See {Yellow}.] [Written also {yelk}.] [1913 Webster] 1. The yellow part of an egg; the vitellus. [1913 Webster] 2. (Zo[ o]l.) An oily… …   The Collaborative International Dictionary of English

  • Yolk cord — Yolk Yolk (y[=o]lk or y[=o]k; 277), n. [OE. yolke, yelke, [yogh]olke, [yogh]elke, AS. geoloca, geoleca, fr. geolu yellow. See {Yellow}.] [Written also {yelk}.] [1913 Webster] 1. The yellow part of an egg; the vitellus. [1913 Webster] 2. (Zo[… …   The Collaborative International Dictionary of English

  • Yolk gland — Yolk Yolk (y[=o]lk or y[=o]k; 277), n. [OE. yolke, yelke, [yogh]olke, [yogh]elke, AS. geoloca, geoleca, fr. geolu yellow. See {Yellow}.] [Written also {yelk}.] [1913 Webster] 1. The yellow part of an egg; the vitellus. [1913 Webster] 2. (Zo[… …   The Collaborative International Dictionary of English

  • yelk — Yolk Yolk (y[=o]lk or y[=o]k; 277), n. [OE. yolke, yelke, [yogh]olke, [yogh]elke, AS. geoloca, geoleca, fr. geolu yellow. See {Yellow}.] [Written also {yelk}.] [1913 Webster] 1. The yellow part of an egg; the vitellus. [1913 Webster] 2. (Zo[… …   The Collaborative International Dictionary of English

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