<p><strong>Adjective</strong></p><ul><li>Sound</li><li>Just</li><li>Well-founded</li><li>A valid reason</li><li>Producing the desired result</li><li>Effective</li><li>A valid antidote for gloom</li><li>Having force, weight, or cogency</li><li>Authoritative</li><li>Legally sound</li><li>Effective, or binding</li><li>Having legal force</li><li>A valid contract</li><li>(Of an argument) so constructed that if the premises are jointly asserted, the conclusion cannot be denied without contradiction</li><li>Synonyms: convincing, logical</li><li>Archaic: robust, well, healthy</li></ul>