Originally Posted by Five
you can run into difficulties wiht that one to.
To some its: tired.
Otehrs its a place where horses go to get that nuts chopped off
Nope - the horse one is wrong. In horse world knackers are either horses only fit for the knackers yard (YARD where nuts are chopped off and in the old days horses stepped into a new career as adhesives) OR Knackers can be the testicles (eg a male horse with no knackers is a gelding!).
I think 'Knackered' meaning tired came from the word being used for broken down horses (signifying their fate and future relationship with envelopes).
These days butchers no longer castrate horses - the vet does it but places where horses are slaughtered for meat are still refered to as 'knackers yard'!!
It's an old world we live in.....
AND IT IS TOO BLOODY HOT!!!