jest (n.) Look up jest at Dictionary.com
early 13c., geste, "narrative of exploits," from Old French geste "action, exploit," from Latin gesta "deeds," neuter plural of gestus, past participle of gerere "to carry, behave, act, perform" (see gest, which preserves the original sense). Sense descended through "idle tale" (late 15c.) to "mocking speech, raillery" (1540s) to "joke" (1550s). Also "a laughing-stock" (1590s). Jest-book is from 1690s.
jest (v.) Look up jest at Dictionary.com
1520s, "to speak in a trifling manner;" 1550s, "to joke, say or do something meant to amuse," from Middle English gesten "recite a tale" (late 14c.), from geste "action, exploit" (see jest (n.)). Related: Jested; jesting.