Tiresome activity removing length of cloth as standard (3)
I believe the answer is:
fag
'standard' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for fag that I've seen before include "Tedious chore" , "Hard work - cigarette (slang)" , "Ciggie" , "He'll do anything you ask" , "an awful bore!" .)