corncob vs corn

corncob and corn both are nouns.

Word	Noun	Adjective	Verb	Adverb
corncob	Yes	No	No	No
corn	Yes	No	Yes	No

corncob (noun)	corn (noun)
the hard cylindrical core that bears the kernels of an ear of corn	something sentimental or trite
	ears of corn that can be prepared and served for human food
	whiskey distilled from a mash of not less than 80 percent corn
	tall annual cereal grass bearing kernels on large ears: widely cultivated in America in many varieties; the principal cereal in Mexico and Central and South America since pre-Columbian times
	(Great Britain) any of various cereal plants (especially the dominant crop of the region--wheat in Great Britain or oats in Scotland and Ireland)
	the dried grains or kernels or corn used as animal feed or ground for meal
	a hard thickening of the skin (especially on the top or sides of the toes) caused by the pressure of ill-fitting shoes

corncob (verb)	corn (verb)
	preserve with large-grained rock salt
	feed (cattle) with corn