Seen in mirror, something black on bed, mister, a silk stocking (10)
I believe the answer is:
aristocrat
'silk stocking' is the definition.
(thesaurus)
'seen in mirror something black on bed mister a' is the wordplay.
'seen in mirror' is a reversal indicator (the letters are reflected back).
'something black' becomes 'tar' (I've seen this in other clues).
'on' says to put letters next to each other.
'bed' becomes 'cot' (cot is a kind of bed).
'mister' becomes 'sir' (both can be used to address a man).
'tar'+'cot'+'sir'+'a'='tarcotsira'
'tarcotsira' written backwards gives 'ARISTOCRAT'.
(Other definitions for aristocrat that I've seen before include "Noble" , "Nobleman" , "What's listed in Debrett" , "Nob" , "toff" .)