rib (n.)

Old English ribb "rib," from Proto-Germanic *rebja- (source also of Old Norse rif, Old Saxon ribbi, Old Frisian ribb, Middle Dutch, Dutch ribbe, Old High German ribba, German Rippe), literally "a covering" (of the cavity of the chest), from PIE *rebh- "to roof, cover" (source also of Greek ereptein "to roof," Old Church Slavonic rebro "rib, reef"). As an item of food from early 15c. Rib joint "brothel" is slang from 1943, probably in reference to Adam's rib (compare rib "woman, wife," attested from 1580s).

rib (v.)

"tease, fool," 1930, apparently from rib (n.); perhaps as a figurative suggestion of poking someone in the ribs. Related: Ribbed; ribbing.