inactivity vs holdup

inactivity and holdup both are nouns.

Word	Noun	Adjective	Verb	Adverb
inactivity	Yes	No	No	No
holdup	Yes	No	No	No

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

inactivity: being inactive; being less active
holdup: the act of delaying; inactivity resulting in something being put off until a later time

Other hyponyms of inactivity include pause, wait, waiting, ease, relaxation, repose, rest, idleness, idling, loafing, delay.

inactivity (noun)	holdup (noun)
being inactive; being less active	robbery at gunpoint
a disposition to remain inactive or inert	the act of delaying; inactivity resulting in something being put off until a later time
the state of being inactive