What's the "een" in Halloween?
early 15c., "public," from Middle French populier (Modern French populaire) and directly from Latin popularis "belonging to the people, general, common; devoted to or accepted by the people; democratic," from populus "people" (see people (n.)).
Meaning "suited to ordinary people" is from 1570s in English; hence, of prices, "low, affordable to average persons" (1859). Meaning "well-liked, admired by the people" is attested from c.1600. Of art, entertainment, etc., "favored by people generally" from 1819 (popular song). Related: Popularly. Popular Front "coalition of Communists, Socialists, and radicals" is from 1936, first in a French context.