Proselytize is to preach your religion or beliefs especially to convert others, or to promote a certain course of action.(verb)
An example of proselytize is when you explain Christian theology to try to convince your Agnostic friend to join the Christian faith.
See proselytize in Webster's New World College Dictionary
See proselytize in American Heritage Dictionary 4
verb pros·e·ly·tized, pros·e·ly·tiz·ing, pros·e·ly·tiz·es verb, intransitive
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