Assemble us in term-break (6)
I believe the answer is:
muster
'assemble' is the definition.
(I've seen this before)
'us in term-break' is the wordplay.
'in' means one lot of letters goes inside another.
'break' indicates anagramming the letters.
'term' with letters rearranged gives 'mter'.
'us' inserted inside 'mter' is 'MUSTER'.
(Other definitions for muster that I've seen before include "a lot of peacocks" , "assembled troops?" , "Gather together, say troops" , "Bring (troops) together" , "Call the troops together" .)