So much for that: Trespass, directed by Joel Schumacher, could very well be her corniest movie yet.
Dermott muttered, "And with it he has to pick up the corniest brogue west of Dublin."
1570s, "full of corn, pertaining to corn, from corn (n.1) + -y (2). Chaucer used it of ale (late 14c.), perhaps to mean "malty." American English slang "old-fashioned, sentimental" is from 1932 (first attested in "Melody Maker"), perhaps originally "something appealing to country folk" (corn-fed in the same sense is attested from 1929). Related: Cornily; corniness.
Overly sentimental; banal; devoted to or expressing old-fashioned moral convictions; cornball
[1930+ Jazz musicians; the writer Mari Sandoz (1896–1966) suggested as possible origin the corn-seed catalogs sent to Midwestern farmers before and after 1900, which were larded with tired old jokes; the jokes were called corn jokes and corny]