deferral vs delay

deferral and delay both are nouns.

Word	Noun	Adjective	Verb	Adverb
deferral	Yes	No	No	No
delay	Yes	No	Yes	No

As nouns, delay is a hypernym of deferral; that is, delay is a word with a broader meaning than deferral:

deferral: act of putting off to a future time
delay: the act of delaying; inactivity resulting in something being put off until a later time

Other hypernyms of deferral include holdup.

deferral (noun)	delay (noun)
act of putting off to a future time	the act of delaying; inactivity resulting in something being put off until a later time
a state of abeyance or suspended business	time during which some action is awaited

deferral (verb)	delay (verb)
	cause to be slowed down or delayed
	stop or halt
	slow the growth or development of
	act later than planned, scheduled, or required