"part of the body where pelvis and thigh join," O.E. hype, from P.Gmc. *khupiz (cf. Du. heup, Ger. Hüfte, Goth. hups "hip"), from PIE *qeub- "to bend." Hipsters "pants that ride on the hips" first attested 1962; hip-huggers in this sense first recorded 1967.
"informed," 1904, apparently originally in black slang, probably a variant of hep, with which it is identical in sense, though it is recorded four years earlier. Hip-hop music style first recorded 1982.
exclamation used to introduce a united cheer (cf. hip-hip-hurrah), 1827, earlier hep, cf. Ger. hepp, to animals a cry to attack, to mobs a cry to attack Jews (see hep (2)); perhaps a natural sound (cf. L. eho, heus).