Forceful macho types must be held in check (8)
I believe the answer is:
vehement
'forceful' is the definition.
(I've seen this before)
'macho types must be held in check' is the wordplay.
I cannot really understand how this works, but
'macho types' could be 'hemen' (a he-man is a muscular man) and 'hemen' is found in the answer.
'be' could be 'vet' (vetting is a kind of being) and 'vet' is found within the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for vehement that I've seen before include "Showing strong feeling, like even them" , "Violent" , "Forcefully emphatic" , "Even them being intense, showing strong feeling" , "Intensely forceful" .)