Patterned knitwear dear — fogy able to get half off repeatedly (6)
I believe the answer is:
argyle
'patterned knitwear' is the definition.
I don't understand how the remainder of the clue works.
(Other definitions for argyle that I've seen before include "Design of diamond shapes, based on a Scottish clan tartan" , "Knitted or woven with diamond-shaped pattern" , "Diamond knitting pattern" , "See 10" , "Diamond-shaped knitting pattern" .)