tum·ble·down 
(tŭmbəl-doun′)
(tŭmbəl-doun′)adj.
Being in such bad repair as to seem in danger of collapsing; very dilapidated or rickety: a tumbledown shack.
- biomathematical
- biomathematician
- biomathematics
- biome
- biomechanical
- biomechanically
- biomechanics
- biomedical
- biomedical engineering
- biomedicine
- biometeorology
- biometric
- biometrical
- biometrically
- biometrics
- biometry
- biomorph
- biomorphic
- biomorphism
- bionic
- bionics
- bionomic
- bionomical
- bionomically
- bionomics