noun (used with a singular verb)
- the first milk or colostrum of a mammal, especially a cow, after giving birth.
- (functioning as singular) the first milk secreted by the mammary glands of a cow or similar animal immediately after giving birth; colostrum
“colostrum,” Old English bysting, from beost, a general West Germanic word (cf. Old High German biost, German Biest, Middle Dutch and Dutch biest, of unknown origin.