unsound
adjective
1. not in good condition; damaged or decayed
- an unsound foundation
Similar word(s): corroded, decayed, rotted, rotten
2. not sound financially
- unsound banking practices
Similar word(s): broken, damaged, unfit, unhealthy, injured, bad, risky, speculative, long, wildcat, unwholesome
3. containing or based on a fallacy
- an unsound argument
Similar word(s): invalid, fallacious
4. suffering from severe mental illness
- of unsound mind
Similar word(s): insane, unstable
5. physically unsound or diseased
- an unsound limb
- unsound teeth
Similar word(s): unhealthy, bad, unfit
6. of e.g. advice
Similar word(s): undependable, unreliable