harpoon

Concise Oxford English Dictionary © 2008 Oxford University Press:
harpoon/hɑːˈpuːn/

▶noun a barbed spear-like missile attached to a long rope and thrown by hand or fired from a gun, used for catching whales and other large sea creatures. ▶verb spear with a harpoon.

– derivatives
harpooner noun.

– origin C17: from Fr. harpon, from harpe ‘dog's claw, clamp’.