To christen is to baptize into a Christian church, or to use something for the first time.
(verb)See christen in Webster's New World College Dictionary
transitive verb
Origin: ME cristnen < OE cristnian: see Christian
See christen in American Heritage Dictionary 4
transitive verb chris·tened, chris·ten·ing, chris·tens
Origin:
Origin: Middle English cristnen
Origin: , from Old English cristnian
Origin: , from cristen, Christian; see Christian
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