harpoon
v.
1774, from harpoon, n.. Related: Harpooned; harpooning. For agent-noun forms, harpooner is from 1726; harpooneer from 1610s.
n.
1610s, from French harpon, from Old French harpon "cramp iron, clamp, clasp" (described as a mason's tool for fastening stones together), from harper "to grapple, grasp," possibly of Germanic origin; or from Latin harpa- "hook" (related to harpagonem "grappling hook"), from Greek harpe "sickle," from PIE root *serp- (1) "sickle, hook." Earlier harping-iron (mid-15c.). Sense and spelling perhaps influenced by Dutch (Middle Dutch harpoen) or Basque, the language of the first whaling peoples, who often accompanied English sailors on their early expeditions. Also see -oon.