introduction vs opening

introduction and opening both are nouns.

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

As nouns, opening is a hyponym of introduction; that is, opening is a word with a more specific, narrower meaning than introduction:

Other hyponyms of introduction include exordium, foreword, preface, prolusion, preamble, prolegomenon, prologue.

introduction (noun)	opening (noun)
the act of putting one thing into another	a recognized sequence of moves at the beginning of a game of chess
the act of beginning something new	the act of opening something
the act of starting something for the first time; introducing something new	becoming open or being made open
the first section of a communication	the first of a series of actions
formally making a person known to another or to the public	a vacant or unobstructed space that is man-made
a basic or elementary instructional text	an entrance equipped with a hatch; especially a passageway between decks of a ship
a new proposal	an aperture or hole that opens into a bodily cavity
	a possible alternative
	the initial part of the introduction
	the first performance (as of a theatrical production)
	a ceremony accompanying the start of some enterprise
	an open or empty space in or between things
	opportunity especially for employment or promotion

introduction (adjective)	opening (adjective)
	first or beginning