Some of the men definitely correct (5)
I believe the answer is:
emend
'correct' is the definition.
(I've seen this before)
'some of the men definitely' is the wordplay.
'some of' indicates a hidden word.
'EMEND' can be found hidden inside 'the men definitely'.
(Other definitions for emend that I've seen before include "Alter to improve (text)" , "get rid of faults" , "would appear better" , "Make improvements or corrections" , "Improve by editing" .)