pause vs rest period

pause and rest period both are nouns.

Word	Noun	Adjective	Verb	Adverb
pause	Yes	No	Yes	No
rest period	Yes	No	No	No

As nouns, rest period is a hyponym of pause; that is, rest period is a word with a more specific, narrower meaning than pause:

pause: a time interval during which there is a temporary cessation of something
rest period: a pause for relaxation

pause (noun)	rest period (noun)
temporary inactivity	a pause for relaxation
a time interval during which there is a temporary cessation of something

pause (verb)	rest period (verb)
cease an action temporarily
interrupt temporarily an activity before continuing