Others rave about one's self-control (9)
I believe the answer is:
restraint
'self-control' is the definition.
(thesaurus)
'others rave about one's' is the wordplay.
'others' becomes 'rest' (I've seen this before).
'rave' becomes 'rant' ('rant' can be a synonym of 'rave').
'about' is an insertion indicator.
'one' becomes 'i' (Roman numeral).
'rant' enclosing 'i' is 'raint'.
'rest'+'raint'='RESTRAINT'
(Other definitions for restraint that I've seen before include "Moderation" , "Controlling measure" , "Control, restriction, curtailment" , "Restriction, limit" , "It keeps someone or something under control" .)