<p><strong>Adjective</strong></p><ul><li>having or exerting great power or force.</li><li>physically strong, as a person: a large, powerful athlete.</li><li>producing great physical effects, as a machine or a blow.</li><li>potent; efficacious: a powerful drug.</li><li>having great effectiveness, as a speech, speaker, description, reason, etc.</li><li>having great power, authority, or influence; mighty: a powerful nation.</li><li>(Chiefly South Midland and Southern U.S.) great in number or amount: a powerful lot of money.</li></ul><p><strong>Synonyms</strong></p><ul><li>strong</li><li>forceful</li><li>effective</li><li>cogent</li><li>forcible</li><li>convincing</li><li>influential</li></ul><p><strong>Antonyms</strong></p><ul><li>weak</li><li>ineffectual</li></ul>