implacable

Merriam-Webster's Word of the Day for July 13, 2026 is: implacable • \im-PLAK-uh-bul\  • adjective Someone or something described as implacable is not capable of being appeased or changed. // The project faced implacable resistance from community members, and is now off the table. See the entry > Examples: “Unlike, say, the globetrotting stories of Ian Fleming or John le Carré, in which victories only temporarily frustrate an implacable foe, [Agatha] Christie’s smaller worlds feel put right when the cover closes or credits roll.” — The Economist, 17 Jan. 2026 Did you know? Implacable is rooted in the Latin verb placare, meaning “to soothe,” but its im- prefix is a variant of the negating prefix in- (as in inactive) and it signals that there’s nothing warm and fuzzy here. Someone or something described as implacable cannot be soothed, which usually means trouble: implacable is most often attached to words like foe, enemy, hatred and hostility. The opposite of implacable is, of course, placable; it means “easily soothed,” but sadly isn’t called upon very often. Another placare word is likely more familiar. Placate means “to soothe or appease”; it’s frequently applied when an angry person is made to feel less so.