Highlight of the Cresta Run (4)
I believe the answer is:
star
'highlight' is the definition.
(thesaurus)
'of the cresta run' is the wordplay.
'of' says the answer is hidden in the clue.
'STAR' can be found hidden inside 'cresta run'.
(Other definitions for star that I've seen before include "Eg, Rigel, Aldebaran" , "- - of Bethlehem" , "Bright" , "Celestial point of light" , "Five-pointed celestial body" .)