stress vs stressor

stress and stressor both are nouns.

Word	Noun	Adjective	Verb	Adverb
stress	Yes	No	Yes	No
stressor	Yes	No	No	No

stress (noun)	stressor (noun)
the relative prominence of a syllable or musical note (especially with regard to stress or pitch)	any agent that causes stress to an organism
(physics) force that produces strain on a physical body
(psychology) a state of mental or emotional strain or suspense
difficulty that causes worry or emotional tension
special emphasis attached to something

stress (verb)	stressor (verb)
to suffer from stress
to stress, single out as important
put stress on; utter with an accent
test the limits of