Top individual appearing in fashion title (7)
I believe the answer is:
caption
'title' is the definition.
(caption is a kind of title)
'top individual appearing in fashion' is the wordplay.
'top' becomes 'cap' (cap is a kind of top).
'individual' becomes 'i'.
'appearing in' indicates putting letters inside.
'fashion' becomes 'ton' (I've seen this before).
'i' going inside 'ton' is 'tion'.
'cap'+'tion'='CAPTION'
(Other definitions for caption that I've seen before include "accompanying message" , "Elegance of dress" , "Provide (a picture) with a title" , "Explanation of an illustration" , "Legend with a photograph" .)