(n.) One who, or that which, aids.

Bible clerk Bible reader acolytus adjutant agent aid aide aide-de-camp aider almoner anagnost assistant attendant auxiliary beadle bedral best man capitular capitulary choir chaplain churchwarden clerk coadjutant coadjutor coadjutress coadjutrix deacon deaconess deputy diaconus doorkeeper elder elderman executive officer exorcist exorcista help helper helpmate helpmeet holy orders lay elder lay reader lector lecturer lieutenant major orders minor orders ostiarius paranymph paraprofessional parish clerk precentor presbyter priest reader ruling elder sacrist sacristan second servant sexton shames sideman sidesman subdeacon subdiaconus succentor suisse supporting actor supporting instrumentalist teaching elder thurifer verger vergeress