You may elicit guffaws if you confuse these two. Elicit is a verb meaning “to bring or draw out something that is latent or potential,” as in Duke Ellington elicited some amazing sounds from his band. By extension you can elicit a truth or principle, as from a discussion or inquiry. Elicit can also mean “to call forth a reaction,” of which a guffaw is a good example. Illicit, on the other hand, is an adjective meaning “unlawful,” as in money acquired by illicit means