Why is the ninth month called September?
Old English butere "butter," general West Germanic (cf. Old Frisian, Old High German butera, German Butter, Dutch boter), an early loan-word from Latin butyrum "butter" (source of Italian burro, Old French burre, French beurre), from Greek boutyron, perhaps literally "cow-cheese," from bous "ox, cow" (see cow (n.)) + tyros "cheese;" but this might be a folk etymology of a Scythian word.
The product was used from an early date in India, Iran and northern Europe, but not in ancient Greece and Rome. Herodotus described it (along with cannabis) among the oddities of the Scythians. Butter-knife attested from 1818.
Old English buterian "spread butter on," from the same source as butter (n.). Figurative meaning "to flatter lavishly" is by 1798 (with up (adv.), in Connelly's Spanish-English dictionary, p.413). Related: Buttered; buttering.
butter but·ter (bŭt'ər)
A soft yellowish or whitish emulsion of butterfat, water, air, and sometimes salt, churned from milk or cream and processed for use in cooking and as a food.
A soft solid having at room temperature a consistency like that of butter.
(Heb. hemah), curdled milk (Gen. 18:8; Judg. 5:25; 2 Sam. 17:29), or butter in the form of the skim of hot milk or cream, called by the Arabs kaimak, a semi-fluid (Job 20:17; 29:6; Deut. 32:14). The words of Prov. 30:33 have been rendered by some "the pressure [not churning] of milk bringeth forth cheese."