|1.||the substance in an animal ovum consisting of protein and fat that nourishes the developing embryoRelated: vitelline|
|2.||a greasy substance secreted by the skin of a sheep and present in the fleece|
|[Old English geoloca, from geolu|
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 (yōk) Pronunciation Key
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.