catchy adj.

c. 1200, "to take, capture," from Anglo-French or Old North French cachier "catch, capture" animals (Old French chacier "hunt, pursue, drive" animals, Modern French chasser "to hunt"), from Vulgar Latin *captiare "try to seize, chase" (also source of Spanish cazar, Italian cacciare), from Latin captare "to take, hold," frequentative of capere "to take, hold" (from PIE root *kap- "to grasp"). A doublet of chase (v.).

Its senses in early Middle English also included "to chase, hunt," which later went with chase (v.). Of sleep, etc., from early 14c.; of infections from 1540s; of fire from 1734 (compare Greek aptō "fasten, join, attach, grasp, touch," also "light, kindle, set on fire, catch on fire"). Related: Catched (obsolete); catching; caught.

The meaning "act as a catcher in baseball" is recorded from 1865. To catch on "apprehend, understand" is by 1884, American English colloquial. To catch the eye "draw the attention" is attested by 1718. Catch as catch can has roots in late 14c. (cacche who that cacche might).

adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.

also catchphrase, "phrase caught up and repeated," 1837, from catch (v.) + phrase (n.). The notion is of words that will "catch" in the mind (compare catchword, which is older and might have suggested this word; also catchy). From the first in a political context, also of lines from plays that became popular.

This new experiment consists in a "divorce of bank and State." This is a mere catch-phrase, which was originally introduced by artful and designing politicians to impose upon the credulity and honesty of the people. Many have adopted it without reflecting or inquiring as to its import, or its consequences. [Sen. Talmage (Georgia), U.S. Senate debate on the Sub-Treasury Bill, Sept. 22, 1837]

In political or partisan squibs, the introduction of such phrases may be properly allowed, though sparingly ; for they are most undoubtedly a species of ornament that soon nauseates upon repetition. There is a still lower species of "slang," consisting of the "catch phrase of the day," in great vogue among the gods at the minor theatres, that we only mention to reprobate entirely ; and which, as common sense is no ingredient in its concoction, is as destitute of energy as it is abhorrent to a cultivated ear. ["T.A.," "Guide for the Writing-Desk; or, Young Author's and Secretary's Friend," etc., London, 1846]