Tack holding rear of carpet is a bother (4)
I believe the answer is:
stew
'a bother' is the definition.
(thesaurus)
'tack holding rear of carpet' is the wordplay.
'tack' becomes 'sew' (I've seen this before).
'holding' indicates putting letters inside.
'rear of' says to take the final letters.
The final letter of 'carpet' is 't'.
'sew' enclosing 't' is 'STEW'.
'is' is the link.
(Other definitions for stew that I've seen before include "Dish cooked by simmering slowly" , "Agitation; food" , "Meat and veg dish" , "State of anxiety; dish" , "Cook by long slow simmering" .)