Nothing in trick to excite (5)
I believe the answer is:
rouse
'to excite' is the definition.
(I've seen this before)
'nothing in trick' is the wordplay.
'nothing' becomes 'O' (O resembles 0).
'in' means one lot of letters goes inside another.
'trick' becomes 'ruse' (I've seen this before).
'o' placed into 'ruse' is 'ROUSE'.
(Other definitions for rouse that I've seen before include "Prod" , "Cause to wake up and come alert" , "Stir up; excite" , "Bestir" , "Waken" .)