milk chickenn.rare a chicken that has been fed on milk and ground oats.
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the world > animals > birds > order Galliformes (fowls) > family Phasianidae (pheasants, etc.) > genus Gallus (domestic fowl) > [noun] > member of (fowl) > fed on particular things
milk chicken1902
1902 Encycl. Brit. XXXI. 882/2 Chickens fattened quite young..and known as petits poussins or ‘milk chickens’.