<p><strong>Adjective</strong></p><ul><li>made hard</li><li>hardened</li></ul><p><strong>Synonyms</strong></p><ul><li>hard</li></ul><p><strong>Antonyms</strong></p><ul><li>soft</li><li>insensitive</li><li>indifferent</li><li>unsympathetic</li></ul><p><strong>Example</strong></p><ul><li>They have a callous attitude toward the sufferings of others.</li></ul><p><strong>Synonyms</strong></p><ul><li>obtuse</li><li>insensible</li></ul><p><strong>Antonyms</strong></p><ul><li>sensitive</li></ul><p><strong>Noun</strong></p><ul><li>having a callus</li><li>indurated, as parts of the skin exposed to friction</li></ul><p><strong>Verb</strong></p><ul><li>to make or become hard or callous</li></ul>