Let out a warning, losing the head and had a row (5)
I believe the answer is:
oared
'let out' is the definition.
The definition suggests an adjective which matches the answer.
'a warning losing the head and had a row' is the wordplay.
I cannot quite see how this works, but
'a' is within the answer.
'had' could be 'd' (I've seen this in other clues) and 'd' is located in the answer.
The remaining letters 'ore' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for oared that I've seen before include "Provided with motive power" , "Rowed" , "Having something to pull on" , "As some boats flew" , "Equipped with rowing blades" .)