<p><strong>Noun:</strong></p><ul><li>Chemistry. Any of certain metallic sulfates of glassy appearance, as copper sulfate or blue vitriol, iron sulfate or green vitriol, zinc sulfate or white vitriol, etc.</li><li>Oil of vitriol; sulfuric acid.</li><li>Something highly caustic or severe in effect, as criticism.</li></ul><p><strong>Verb:</strong></p><ul><li>(used with object) vitrioled, vitrioling or (especially British) vitriollled, vitriolling.</li><li>To treat with or as with vitriol, especially sulfuric acid.</li></ul>