Cool men adapted eyeglass (7)
I believe the answer is:
monocle
'eyeglass' is the definition.
(I know that eyeglass can be written as monocle)
'cool men adapted' is the wordplay.
'adapted' is an anagram indicator.
'cool'+'men'='coolmen'
'coolmen' anagrammed gives 'MONOCLE'.
(Other definitions for monocle that I've seen before include "Reading glass for one eye only" , "optical device" , "lens" , "Single eyeglass" , "One-lens seeing apparatus" .)