wear out vs wear down

wear out and wear down both are verbs.

Word	Noun	Adjective	Verb	Adverb
wear out	No	No	Yes	No
wear down	No	No	Yes	No

As verbs, wear out and wear down are synonyms defined as:

wear out and wear down: exhaust or get tired through overuse or great strain or stress

Other synonyms of wear out include fag, fag out, fatigue, jade, outwear, tire, tire out, wear, wear upon, weary.

As verbs, wear out and wear down are synonyms defined as:

Other synonyms of wear out include wear, wear off, wear thin.

wear out (verb)	wear down (verb)
exhaust or get tired through overuse or great strain or stress	exhaust or get tired through overuse or great strain or stress
deteriorate through use or stress	deteriorate through use or stress
go to pieces