Nouns

(n)organizer, organiser, labor organizersomeone who enlists workers to join a union
(n)organizer, organiser, arrangera person who brings order and organization to an enterprise“she was the organizer of the meeting”
(n)personal digital assistant, PDA, personal organizer, personal organiser, organizer, organisera lightweight consumer electronic device that looks like a hand-held computer but instead performs specific tasks; can serve as a diary or a personal database or a telephone or an alarm clock etc.