Definition of yolk in US English:



  • 1The yellow internal part of a bird's egg, which is surrounded by the white, is rich in protein and fat, and nourishes the developing embryo.

    • ‘Fold the egg whites into the egg yolk and sugar mixture.’
    • ‘In bowl, whisk together sugar and yolks until light yellow and foamy.’
    • ‘The eggs were then cracked open, and the yolks and whites of the egg samples from the same batch were pooled and homogenized with an electric mixer.’
    • ‘Leftover raw egg whites and yolks should be put in airtight containers and refrigerated immediately, then used within a day or two.’
    • ‘Mix egg yolk and lemon juice, add to flour mixture, and mix to a stiff dough’
    • ‘Cool and peel eggs, reserving yolks and discarding whites.’
    • ‘Use hands to slowly incorporate yolks into potato and flour mixture.’
    • ‘Gently drizzle vinegar over yolks and sprinkle sugar and salt on top.’
    • ‘Whole egg protein contains yolks and whites, providing a high ratio of indispensable amino acids.’
    • ‘When the whites congeal, just spoon some water over the yellow yolks and the albumen will turn white, and you have your runny eggs.’
    • ‘Mix the egg yolk, milk, sugar and potato flour together in a small saucepan.’
    • ‘Fresh eggs from free-range chickens will produce a stronger binder because of the rich, viscous yolks.’
    • ‘Separate egg whites and yolks into separate bowls.’
    • ‘Put the rind, juice, yolks and sugar in a small basin and place over a pan of boiling water.’
    • ‘Gradually pour half of hot milk mixture over yolks while whisking constantly.’
    • ‘To make the custard, separate the eggs and whisk the vanilla sugar into the yolks (save the whites for meringues).’
    • ‘The yolks were homogenized with 1 ml water per gram of yolk.’
    • ‘These new noodles substitute soy flour for semolina flour and may contain egg whites or yolks to boost protein.’
    • ‘You may be used to eating the whites and discarding the yolks, but skip that step during pregnancy because the yolks provide extra calories, Vitamin D and folic acid.’
    • ‘The preserved eggs, with their green-and-yellow yolks and amber whites, cut into segments and arranged around a pile of chopped green peppers like the petals of a flower.’
    1. 1.1Zoology The corresponding part in the ovum or larva of all egg-laying vertebrates and many invertebrates.
      • ‘In contrast to the fluid yolk of atherinomorphs, yolk is organized into globules in other taxa.’
      • ‘In this study, we investigated differences in maternally deposited yolk testosterone and DHT in relation to diet quality.’
      • ‘For example, yolk was present in male blood plasma, which is highly abnormal.’
      • ‘Fleischer used gel electrophoresis to discriminate yolk allozymes sampled from eggs laid by several female cowbirds.’
      • ‘An estimate of the daily amount of yolk deposited on developing ova and the sequence of laying are important when evaluating the total cost of egg production.’


Old English geol(o)ca, from geolu ‘yellow’.