The definition of a yolk is the yellow part of an egg.(noun)
An example of a yolk is the part you remove to make an egg white omelet.
See yolk in Webster's New World College Dictionary
Origin: ME yolke < OE geolca, yolk, lit., yellow part, akin to geolu, yellow
See yolk in American Heritage Dictionary 4
Origin: Middle English yolke
Origin: , from Old English geolca
Origin: , from geolu, yellow; see yellow.
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