Not busy, for short (5)
I believe the answer is:
avail
(Other definitions for avail that I've seen before include "Be of value to" , "Be of service to" , "Help, benefit" , "Be useful" , "Use to one's advantage" .)
I believe the answer is:
avail
(Other definitions for avail that I've seen before include "Be of value to" , "Be of service to" , "Help, benefit" , "Be useful" , "Use to one's advantage" .)