The sheep a fathead has to make secure? (5)
I believe the answer is:
flock
'the sheep' is the definition.
(a group of sheep)
'a fathead has to make secure?' is the wordplay.
I cannot really understand how this works, but
'fathead' could be 'f' (head letter of 'fat') and 'f' is found within the answer.
'secure?' could be 'lock' (locking is a kind of securing) and 'lock' is present in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for flock that I've seen before include "Raised-pattern (wallpaper)" , "Congregation" , "Group of sheep or birds" , "A number of sheep" , "Bevy" .)