Convener, one coming in daily (5)
I believe the answer is:
chair
'convener' is the definition.
(thesaurus)
'one coming in daily' is the wordplay.
'one' becomes 'i' (Roman numeral).
'coming in' indicates putting letters inside.
'daily' becomes 'char' (both can mean a cleaner).
'i' going inside 'char' is 'CHAIR'.
(Other definitions for chair that I've seen before include "conduct" , "Preside, guide meeting" , "Presiding officer" , "Supporter" , "director at meeting" .)