Brief coalition between opponents becomes apparent (7)
I believe the answer is:
emerges
'becomes apparent' is the definition.
I can't tell whether this definition defines the answer.
'brief coalition between opponents' is the wordplay.
'brief coalition' becomes 'merge' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'between' indicates putting letters inside.
'opponents' becomes 'es' (I've seen this in other clues).
'merge' put into 'es' is 'EMERGES'.
Can you help me to learn more?
(Other definitions for emerges that I've seen before include "Comes out" , "Issues" , "Turns out" , "appears" .)