delay vs hold off

delay is a noun but hold off is not a noun.

Word	Noun	Adjective	Verb	Adverb
delay	Yes	No	Yes	No
hold off	No	No	Yes	No

As verbs, hold off is a hypernym of delay; that is, hold off is a word with a broader meaning than delay:

Other hypernyms of delay include hold back, wait.

delay (noun)	hold off (noun)
the act of delaying; inactivity resulting in something being put off until a later time
time during which some action is awaited

delay (verb)	hold off (verb)
cause to be slowed down or delayed	resist and fight to a standoff
stop or halt	wait before acting
slow the growth or development of
act later than planned, scheduled, or required