opening vs start

opening and start both are nouns.

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

As nouns, start is a hypernym of opening; that is, start is a word with a broader meaning than opening:

Other hypernyms of opening include beginning, commencement.

As nouns, start is a hypernym of opening; that is, start is a word with a broader meaning than opening:

opening (noun)	start (noun)
a recognized sequence of moves at the beginning of a game of chess	the act of starting something
the act of opening something	a sudden involuntary movement
becoming open or being made open	a turn to be a starter (in a game at the beginning)
the first of a series of actions	the advantage gained by beginning early (as in a race)
a vacant or unobstructed space that is man-made	a signal to begin (as in a race)
an entrance equipped with a hatch; especially a passageway between decks of a ship	the beginning of anything
an aperture or hole that opens into a bodily cavity	a line indicating the location of the start of a race or a game
a possible alternative	the time at which something is supposed to begin
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

opening (adjective)	start (adjective)
first or beginning

opening (verb)	start (verb)
	take the first step or steps in carrying out an action
	set in motion, cause to start
	play in the starting lineup
	bring into being
	get off the ground
	begin or set in motion
	get going or set in motion
	depart for someplace
	bulge outward
	move or jump suddenly, as if in surprise or alarm
	begin work or acting in a certain capacity, office or job
	begin an event that is implied and limited by the nature or inherent function of the direct object
	have a beginning, in a temporal, spatial, or evaluative sense
	have a beginning characterized in some specified way