Issue for millennials, in short (7)
I believe the answer is:
progeny
'issue' is the definition.
(I know that issue can be written as progeny)
'for millennials in short' is the wordplay.
I cannot really see how this works, but
'for' could be 'pro' (as in being 'pro' or in favour of something) and 'pro' is located in the answer.
'millennials' could be 'geny' (Gen Y can refer to the millennial generation) and 'geny' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for progeny that I've seen before include "seed?" , "Children" , "Issue, offspring" .)