Gloss woman's brought to old gallery (8)
I believe the answer is:
annotate
'gloss' is the definition.
(thesaurus)
'woman's brought to old gallery' is the wordplay.
'woman' becomes 'ann'.
'brought to' is a charade indicator (letters next to each other).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'gallery' becomes 'tate' (I've seen this before).
'ann'+'o'+'tate'='ANNOTATE'
(Other definitions for annotate that I've seen before include "Provide interlinear or marginal comments in a book" , "Add explanations and comments to (a text)" , "Write down comments on" , "Add notes to (text)" , "Supply explanatory notes" .)