Nouns

(n)organizer, organiser, arrangera person who brings order and organization to an enterprise“she was the organizer of the meeting”
(n)organizer, organiser, labor organizersomeone who enlists workers to join a union
(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.