The definition of marry is to become wedded to someone and become a husband or wife, or the act of pronouncing a couple as wed, or the act of joining two things together.(verb)
When you give someone a wedding ring and say "I do," this is an example of a situation where you marry.
See marry in Webster's New World College Dictionary
Origin: ME marien < OFr marier < L maritare < maritus, a husband, married, prob. < IE base *meri, young wife, akin to *meryo, young man > Sans márya-, man, young man, suitor
Origin: euphemistic respelling of (the Virgin) Mary
See marry in American Heritage Dictionary 4
verb mar·ried, mar·ry·ing, mar·ries verb, transitive
Origin: Middle English marien
Origin: , from Old French marier
Origin: , from Latin marītāre
Origin: , from marītus, married.
Origin: Middle English Marie, the Virgin Mary
Origin: , ultimately from Greek Maria; see Mary1.
Learn more about marry