Inhibition of one in holiday rave (9)
I believe the answer is:
restraint
'inhibition' is the definition.
(thesaurus)
'one in holiday rave' is the wordplay.
'one' becomes 'i' (roman numeral).
'in' is an insertion indicator.
'holiday' becomes 'rest' (I've seen this before).
'rave' becomes 'rant' (synonyms).
'rest'+'rant'='restrant'
'i' going within 'restrant' is 'RESTRAINT'.
'of' acts as a link.
(Other definitions for restraint that I've seen before include "It keeps someone or something under control" , "Controlling measure" , "Reserve" , "Check" , "controlling influence" .)