use vs exercise

use and exercise both are nouns.

Word	Noun	Adjective	Verb	Adverb
use	Yes	No	Yes	No
exercise	Yes	No	Yes	No

As nouns, use and exercise are synonyms defined as:

Other synonyms of use include employment, usage, utilisation, utilization.

As verbs, exercise is a hyponym of use; that is, exercise is a word with a more specific, narrower meaning than use:

use: put into service; make work or employ for a particular purpose or for its inherent or natural purpose
exercise: put to use

use (noun)	exercise (noun)
the act of using	the activity of exerting your muscles in various ways to keep fit
(psychology) an automatic pattern of behavior in reaction to a specific situation; may be inherited or acquired through frequent repetition	a task performed or problem solved in order to develop skill or understanding
exerting shrewd or devious influence especially for one's own advantage	systematic training by multiple repetitions
what something is used for	the act of using
a particular service	an action, often used negatively and without consequences
(law) the exercise of the legal right to enjoy the benefits of owning property	(usually plural) a ceremony that involves processions and speeches
(economics) the utilization of economic goods to satisfy needs or in manufacturing

use (verb)	exercise (verb)
put into service; make work or employ for a particular purpose or for its inherent or natural purpose	do physical exercise
take or consume (regularly or habitually)	give a workout to
use up (resources or materials)	learn by repetition
habitually do something or be in a certain state or place (use only in the past tense)	put to use
avail oneself to	carry out or practice; as of jobs and professions
seek or achieve an end by using to one's advantage