Something musical beat film (7)
'something musical' is the definition.
(trumpet is a kind of musical instrument)
'beat film' is the wordplay.
'beat' becomes 'trump' (both can mean to better or defeat).
'film' becomes 'ET' (E.T. the Extra-Terrestrial).
'trump'+'et'='TRUMPET'
(Other definitions for trumpet that I've seen before include "Shout!" , "Loud cry" , "Play it" , "Brass wind instrument" , "Head" .)
'something musical' is the definition.
(I've seen this before)
'beat film' is the wordplay.
'beat' becomes 'intro' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'film' becomes 'It'.
'intro'+'it'='INTROIT'
Can you help me to learn more?
(Other definitions for introit that I've seen before include "Something musical" , "Anthem sung at beginning of Mass" , "Pre-Eucharist prayer" , "Church psalm" , "chant" .)