Lynn's upset about old stockings (6)
I believe the answer is:
nylons
'stockings' is the definition.
(I've seen this in another clue)
'lynn's upset about old' is the wordplay.
'upset' indicates an anagram.
'about' means one lot of letters goes inside another.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'lynns' anagrammed gives 'nylns'.
'nylns' placed around 'o' is 'NYLONS'.
(Other definitions for nylons that I've seen before include "Silk-like stockings" , "Women's stockings made of synthetic material" , "may have ladders" , "Sheer stockings for women" , "Hosiery" .)