Knackered

From the verb knacker.

Full definition of knackered

(UK, Irish, Australia, New Zealand, slang) tired or exhausted.I can't go out tonight — I'm knackered.

2002, Robert Edenborough, Effective Interviewing: A Handbook of Skills and Techniques, pages 97-98I've got this job in a warehouse just now and it finishes quite early but I'm dead knackered at the end of the day so I don't know about going out and like studying every night.
2003, Hugh Dauncey, Geoff Hare (editors), The Tour de France, 1903-2003: A Century of Sporting Structures, Meanings and Values, Frank Cass Publishers, London, 2005, most+knackered%22+-intitle:%22%22+-inauthor:%22%22&hl=en&sa=X&ei=SfuXT8P-HLCYiAfDqunVBQ&redir_esc=y#v=onepage&q=%22more|most%20knackered%22%20-intitle%3A%22%22%20-inauthor%3A%22%22&f=false page 225,Then, it all just gets worse and worse, you donâ€²t sleep so much, so you donâ€²t recover as well from the dayâ€²s racing, so you go into your reserves, you get more knackered, so you sleep less... Itâ€²s simply a vicious circle.
2009, Grace Maxwell, Falling & Laughing: The Restoration of Edwyn Collins, page 84,So my joy at hearing his voice quickly turns to a paroxysm of anxiety as he manages by exhausted gesture and sound to let us know how knackered he feels, how desperate to get horizontal, almost from the first moment he lands in the chair.

Rarely used in North America, where the usage is lessâ€well unknown.

knackered

From "ready for the knacker's yard" or "fit to be knackered", meaning "worn-out livestock, fit to be slaughtered and rendered".

2003, Simon Murphy, The Murders of Mutchrose Village, In the end though he had to admit that the car was knackered...
2009, John Newton, Vance Miller - Kitchen Gangster?, page 82We take an old knackered machine out to China and say, 'Copy that, brand new,' and they do.