Rebellious tribe in America kill unit deprived of cover (5)
I believe the answer is:
iceni
'rebellious tribe' is the definition.
(I've seen this before)
'america kill unit deprived of cover' is the wordplay.
I cannot quite understand how this works, but
'kill' could be 'ice' (ice can informally mean to assassinate) and 'ice' is present in the answer.
'unit' could be 'n' (N is an example) and 'n' is found within the answer.
A single letter 'i' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'in' is the link.
Can you help me to learn more?
(Other definitions for iceni that I've seen before include "Boudicca's tribe" , "Old warriors" , "Ancient British tribe" , "Ancient tribesmen" , "Boadicea's tribe" .)