Antelopes with nothing to eat in reserves (5)
I believe the answer is:
books
'reserves' is the definition.
(booking is a kind of reserving)
'antelopes with nothing to eat' is the wordplay.
I cannot really see how this works, but
'nothing' could be 'o' (O resembles 0) and 'o' is located in the answer.
The remaining letters 'boks' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'in' acts as a link.
(Other definitions for books that I've seen before include "Reserve tickets" , "See 1" , "Reserves" , "Tomes, volumes" .)