run-down vs decrepit

run-down and decrepit both are adjectives.

Word	Noun	Adjective	Verb	Adverb
run-down	No	Yes	No	No
decrepit	No	Yes	No	No

As adjectives, run-down and decrepit are synonyms defined as:

Other synonyms of run-down include creaky, derelict, flea-bitten, woebegone.

run-down (adjective)	decrepit (adjective)
having the spring unwound	lacking bodily or muscular strength or vitality
worn and broken down by hard use	worn and broken down by hard use