ə̇ˈnishēˌād.ə(r), -ātə- sometimes -isē- noun
( -s )
Etymology: Late Latin, from Latin initiatus (past participle of initiare to initiate) + -or — more at initiate
: one that initiates: as
a. : a person who originates or sets on foot some process or movement
a great initiator in art
b. : detonator c
c. : a substance that initiates a reaction
benzoyl peroxide is used as an initiator in polymerization
— compare catalyst 1