"weapon with a penetrating head and a long wooden shaft, meant to be thrust or thrown," Old English spere "spear, javelin, lance," from Proto-Germanic *sperō (source also of Old Norse spjör, Old Saxon, Old Frisian sper, Dutch speer, Old High German sper, German Speer "spear"), from PIE root *sper- (1) "spear, pole" (source also of Old Norse sparri "spar, rafter," and perhaps also Latin sparus "hunting spear").
pike-like fish, 1765, American English, shortening of garfish (mid-15c.), from fish (n.) + Middle English gare, gore "a spear," from Old English gar "spear," from Proto-Germanic *gaisa- "spear" (source also of Old Norse geirr "spear; point of an anvil," Old Saxon, Old High German ger, German Ger "spear"), from PIE *ghaiso- "a stick, spear" (see goad (n.)). The fish so called for its long sharp snout. Compare Edgar, garlic.