Public toilets, just half serving men, one gathers (8)
I believe the answer is:
convenor
'one gathers' is the definition.
(someone who convenes or gathers)
'public toilets just half serving men' is the wordplay.
'public toilets' becomes 'conveniences' ('convenience' can be a synonym of 'public toilet').
'just half' means to take half the letters.
'serving men' becomes 'OR' (military abbreviation for Other Ranks).
'conveniences' halved is 'conven'.
'conven'+'or'='CONVENOR'
(Other definitions for convenor that I've seen before include "The member who calls the meetings" , "One who gathers poeple for a meeting" , "The one who organises meetings" , "Chair of meeting" , "One who calls a meeting" .)