intromission vs introduction

intromission and introduction both are nouns.

Word	Noun	Adjective	Verb	Adverb
intromission	Yes	No	No	No
introduction	Yes	No	No	No

As nouns, intromission and introduction are synonyms defined as:

intromission and introduction: the act of putting one thing into another

Other synonyms of intromission include insertion.

intromission (noun)	introduction (noun)
the act of putting one thing into another	the act of putting one thing into another
	the act of beginning something new
	the act of starting something for the first time; introducing something new
	the first section of a communication
	formally making a person known to another or to the public
	a basic or elementary instructional text
	a new proposal