early 15c., "to deceive;" mid-15c. "make fun of," from Old French mocquer "deride, jeer," of unknown origin, perhaps from Vulgar Latin *muccare "to blow the nose" (as a derisive gesture), from Latin mucus; or possibly from Middle Dutch mocken "to mumble" or Middle Low German mucken "grumble." Or perhaps simply imitative of such speech. Related: Mocked; mocking; mockingly. Replaced Old English bysmerian. Sense of "imitating," as in mockingbird and mock turtle (1763), is from notion of derisive imitation.
1540s, from mock, verb and noun. Mock-heroic is attested from 1711; mock-turtle "calf's head dressed to resemble a turtle," is from 1763; as a kind of soup from 1783.
"derisive action or speech," early 15c., from mock (v.).