Knackered is derived from the past participle of knacker, a slang term meaning "to kill," as well as "to tire, exhaust, or wear out." The origins of the verb knacker are uncertain, but the word is perhaps related to an older noun knacker, which originally referred to a harness-maker or saddlemaker, and later referred to a buyer of animals no longer able to do farmwork (or their carcasses) as well as to a buyer of old structures. The origins of the noun knacker, however, remain obscure. Knackered is used on both sides of the Atlantic but is more common among British speakers.
She was too knackered to join them for dinner. I'm absolutely knackered, so no pub-crawling for me tonight.
Recent Examples on the WebThe adrenaline from having our first child (and keeping him alive) got me through the first several days without feeling completely knackered, but my lack of nocturnal restoration eventually took its toll. Patrick Wilson, Outside Online, 15 June 2020 And, if their knees get too knackered, there’s a backup Santa.Washington Post, 22 Nov. 2021 Mounting a knackered horse and dragging a fat old farmer, Sancho, in his wake, the don declares undying love for an ordinary girl out of her depth. Jeanette Winterson, New York Times, 3 Sep. 2019
English slang knacker to kill, tire, perhaps from knacker, noun