1520s, "chatter, frivolous talk;" see chat (v.). Meaning "familiar conversation" is from 1570s. As a name for birds with chattering cries, 1690s. Chat show for what in U.S. is a talk show is attested from 1967. Chat room in the online sense is attested by 1994, from the days when AOL ruled the World Wide Web.
mid-15c., "talk idly, babble," short for chatter (v.). Meaning "to converse familiarly" is from 1550s. Sense of "flirt with, ingratiate oneself with" (later often with up (adv.)) is from 1898. Related: Chatted; chatting.
also chitchat, "familiar or trivial talk, gossip," 1710, diminishing reduplicated form of chat. The verb is attested from 1821. Related: Chit-chatting.
"changing in luster or color," like a cat's eye in the dark, 1816, from French chatoyant, past participle of chatoyer, from chat "cat" (see cat (n.)).
also shmooze, "to chat intimately," 1897 (schmoos), from Yiddish shmuesn "to chat," from shmues "idle talk, chat," from Hebrew shemu'oth "news, rumors." As a noun from 1939. Related: Schmoozed; schmoozing. Agent noun schmoozer is by 1909.
by 1993, online chat abbreviation for rolling on the floor laughing.
1884, colloquial shortening of congratulations. Further colloquialized in British university slang to congratters (1895) and in online gamer chat shortened to grats (by 2000).
