Yolk

имя существительное желток (яйца)

Большой англо-русский словарь

Yolk

биология желток яйца; желтковый, желточный

Англо-русский научно-технический словарь

Yolk

also yoke noun Etymology: Middle English yolke, from Old English geoloca, from geolu yellow — more at yellow 1. a. the yellow spheroidal mass of stored food that forms the inner portion of the egg of a bird or reptile and is surrounded by the white — see egg illustration b. archaic the whole contents of an animal ovum consisting of a protoplasmic formative portion and an inert nutritive portion c. material stored in an animal ovum that supplies food to the developing embryo and consists chiefly of proteins, lecithin, and cholesterol 2. [akin to Middle Dutch ieke yolk (of wool), Old English ēowu ewe] oily material in unprocessed sheep wool consisting of wool fat, suint, and debris • yolked adjectiveyolky adjective

Merriam-Webster's Collegiate Dictionary