Cross set in elaborate style (5)
I believe the answer is:
testy
'cross' is the definition.
(I've seen this before)
'set in elaborate style' is the wordplay.
'set in' indicates a hidden word.
'TESTY' can be found hidden inside 'elaborate style'.
(Other definitions for testy that I've seen before include "Cross" , "bad temper" , "Irritably impatient" , "Quick to anger" , "Showing irritation" .)