Stand out function held outside hotel (5)
I believe the answer is:
shine
'stand out' is the definition.
(I've seen this in another clue)
'function held outside hotel' is the wordplay.
'function' becomes 'sine' (mathematical function).
'held outside' indicates putting letters inside.
'hotel' becomes 'h' (phonetic alphabet: alpha, bravo, charlie etc.).
'sine' going around 'h' is 'SHINE'.
(Other definitions for shine that I've seen before include "Radiate or excel" , "Glow; polish" , "Give out light; polish" , "Mislaying" , "Direct (a torch) somewhere" .)