As nouns the difference between proposer and initiator
is that proposer is someone who proposes, someone who makes a proposal while initiator is initiator.
proposer
English
Noun
(
en noun)
Someone who proposes, someone who makes a proposal.
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initiator
English
Noun
(
en noun)
One who initiates
(chemistry) A substance that initiates a chain reaction or polymerization
(computing) A task (in a mainframe computer) that initiates multiple jobs
(medicine) A material whose presence in the body eventually leads to cancer