One who initiates. / (chemistry) A substance that initiates a chain reaction or polymerization.

plural of initiator

simple past tense and past participle of initial

present participle of initial

The act of adding one's initials to a document rather than signing

To assign initial values to something / (computing) To assign an initial value to a variable / (computing) To format a storage medium prior to use

present participle of initiate

present participle of initialize

simple past tense and past participle of initialize

plural of initiation