Beauty exposed ugly affair (7)
I believe the answer is:
glamour
'beauty' is the definition.
(I know that glamour is a type of beauty)
'exposed ugly affair' is the wordplay.
'exposed' says to take the centre (the inside of the word is exposed).
'affair' becomes 'amour' (amour can mean a love affair).
The middle letters of 'ugly' are 'gl'.
'gl'+'amour'='GLAMOUR'
(Other definitions for glamour that I've seen before include "Voluptuous allure" , "appeal" , "Charm and allure" , "Attractive and exciting quality" , "model's allure?" .)