tallow UK /ˈtæləʊ/US /ˈtæloʊ/verb 3noun 1forms 3 verb3 •To grease or smear with tallow. •To cause to have a large quantity of tallow; to fatten. •Of animals: to develop quantities of tallow.[…] their beef is finer than that of the old short-horned breed, and they fatten much earlier and quicker, conveying still a vast depth of natural flesh, and tallowing within in the first degree. — 1824 noun1 •A hard animal fat obtained from suet, etc.; used in cooking as well as to make candles, soap and lubricants."I have got a very fine shirt, which I am going to use for my wedding shirt; but there are three tallow stains on it which I want washed out[.]" — 1886 formstallowed · tallowing · tallows