<p><strong>Adjective</strong></p><ul><li>Of, relating to, or characterized by intensity: intensive questioning.</li><li>Tending to intensify; intensifying.</li><li>Medicine/Medical: Increasing in intensity or degree.</li><li>Instituting treatment to the limit of safety.</li><li>Noting or pertaining to a system of agriculture involving the cultivation of limited areas, and relying on the maximum use of labor and expenditures to raise the crop yield per unit area (extensive).</li><li>Requiring or having a high concentration of a specified quality or element (used in combination): Coal mining is a labor-intensive industry.</li><li>Grammar: Indicating increased emphasis or force.</li><li>Certainly is an intensive adverb.</li><li>Myself in I did it myself is an intensive pronoun.</li></ul><p><strong>Noun</strong></p><ul><li>Something that intensifies.</li><li>Grammar: An intensive element or formation, as -self in himself, or Latin -tō in iac-tō, “I hurl” from iacō, “I throw.”</li></ul>