missionary vs missioner

missionary and missioner both are nouns.

Word	Noun	Adjective	Verb	Adverb
missionary	Yes	Yes	No	No
missioner	Yes	No	No	No

As nouns, missionary and missioner are synonyms defined as:

missionary and missioner: someone sent on a mission--especially a religious or charitable mission to a foreign country

missionary (noun)	missioner (noun)
someone who attempts to convert others to a particular doctrine or program	someone sent on a mission--especially a religious or charitable mission to a foreign country
someone sent on a mission--especially a religious or charitable mission to a foreign country

missionary (adjective)	missioner (adjective)
relating to or connected to a religious mission