<p><strong>Adjective</strong></p><ul><li>In the form of an X; crossed; intersected.</li><li>Botany: Arranged along the stem in pairs, each pair at right angles to the pair next above or below, as leaves.</li></ul><p><strong>Verb</strong></p><ul><li>To intersect; cross in the form of an X: About 75 percent of these nerve fibers decussate in the medulla.</li></ul>