delay vs hold over

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

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

As verbs, hold over is a hyponym of delay; that is, hold over is a word with a more specific, narrower meaning than delay:

delay (noun)	hold over (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 over (verb)
cause to be slowed down or delayed	intimidate somebody (with a threat)
stop or halt	hold over goods to be sold for the next season
slow the growth or development of	keep in a position or state from an earlier period of time
act later than planned, scheduled, or required	continue a term of office past the normal period of time
	hold back to a later time