Iron clothes clerk ordered for Mark (7)
I believe the answer is:
freckle
'mark' is the definition.
(I've seen this before)
'iron clothes clerk ordered' is the wordplay.
'iron' becomes 'Fe' (Fe is the chemical symbol for iron).
'clothes' is an insertion indicator (inserted letters are clothed in others).
'ordered' is an anagram indicator.
'clerk' is an anagram of 'reckl'.
'fe' placed around 'reckl' is 'FRECKLE'.
'for' is the link.
(Other definitions for freckle that I've seen before include "Small skin spot" , "Lentigo" , "Brown mark on the skin" , "Brown spot on skin" .)