yolk

[yohk, yohlk] /yoʊk, yoʊlk/
noun
1.
the yellow and principal substance of an egg, as distinguished from the white.
2.
Embryology. the part of the contents of the egg of an animal that enters directly into the formation of the embryo, together with any material that nourishes the embryo during its formation.
3.
the essential part; the inner core.
4.
a natural grease exuded from the skin of sheep.
Also, yoke.
Origin
before 1000; Middle English yolke, yelke, Old English geoloca, derivative of geolu yellow
Related forms
yolked, adjective
yolkless, adjective
yolky, adjective
Can be confused
yoke, yolk.
Examples from the web for yolk
  • The cost of a lifetime spent opening eggs incompetently is a small amount of wasted time and some spilled yolk.
  • The raw egg starts to spin again because it has liquid yolk and egg white inside.
  • Inside the pouch, the tadpoles live on the yolk leftover from their hatching.
  • Scavengers such as crickets might have fed on the yolk, and spiders later dined on the scavengers.
  • Revelers eat traditional moon cakes filled with lotus seed and salted egg yolk, or one of many newer varieties.
  • Because the yolk contains fat, it floats above the aqueous white, both in the shell and in a beaker.
  • To achieve a centered yolk, one must rotate the egg while cooking it.
  • At the junction of the yolk-sac and body-stalk each vein is joined by a branch from the vascular plexus of the yolk-sac.
  • Beat the egg yolk with remaining milk and brush on the scones.
  • Brush with the egg yolk mixture and place on the prepared baking sheet.
British Dictionary definitions for yolk

yolk

/jəʊk/
noun
1.
the substance in an animal ovum consisting of protein and fat that nourishes the developing embryo related adjective vitelline
2.
a greasy substance secreted by the skin of a sheep and present in the fleece
Derived Forms
yolkless, adjective
yolky, adjective
Word Origin
Old English geoloca, from geoluyellow
Word Origin and History for yolk

Old English geolca, geoloca "yolk," literally "the yellow part," from geolu "yellow" (see yellow). Formerly also spelled yelk.

yolk in Medicine

yolk (yōk)
n.
The portion of the egg of an animal that consists of protein and fat from which the early embryo gets its main nourishment and of protoplasmic substances from which the embryo develops.

yolk in Science
yolk
  (yōk)   
The yellow internal part of the egg of a bird or reptile. The yolk is surrounded by the albumen and supplies food to the developing young.
Encyclopedia Article for yolk

egg yolk

the nutritive material of an egg, used as food by a developing, embryonic animal. Eggs with relatively little, uniformly distributed yolk are termed isolecithal. This condition occurs in invertebrates and in all but the lowest mammals. Eggs with abundant yolk concentrated in one hemisphere of the egg are termed telolecithal. This occurs in many invertebrates and in all vertebrates lower than marsupial mammals. In arthropods, the yolk is massed near the centre of the egg; such eggs are termed centrolecithal

Learn more about egg yolk with a free trial on Britannica.com