de-crep-it / dĭ-krĕp-ĭt
1. weak and worn out due to old age; feeble
There is room in our ranks for the old and decrepit, as well as the young and vigorous.
Gerrit Smith, 1797 – 1874
2. worn out or broken down due to long, hard use; falling apart; shabby
An enterprising person is one who drives through an old decrepit part of town and sees a new housing development.
Jim Rohn, 1930 – 2009
From the Latin adjective decrepitus, decrepita, decrepitum (very old, worn out, collapsed), probably a combination of the past passive participle of the Latin verb crepo, crepare, crepui, crepitum (rattle, creak, crack, fall with a clatter, cause to fall with a loud noise) and the Latin prepositional prefix de (down, down from).
Thank you to Allen Ward for providing the etymology of decrepit.