"landing place, place where vessels are loaded and unloaded, a wharf," 1690s, a spelling variant of Middle English key, keye, caye "wharf" (c. 1300; mid-13c. in place names), from Old North French cai (Old French chai, 12c., Modern French quai) "sand bank," from Gaulish caium (5c.), from Old Celtic *kagio- "to encompass, enclose" (source also of Welsh cae "fence, hedge," Cornish ke "hedge"), from PIE root *kagh- "to catch, seize; wickerwork, fence" (see hedge (n.)). Spelling altered in English by influence of French quai.
updated on March 02, 2021