<p><strong>Noun</strong></p><ul><li>division into two parts, kinds, etc.; subdivision into halves or pairs.</li><li>division into two mutually exclusive, opposed, or contradictory groups: a dichotomy between thought and action.</li><li>Botany: a mode of branching by constant forking, as in some stems, in veins of leaves, etc.</li><li>Astronomy: the phase of the moon or of an inferior planet when half of its disk is visible.</li></ul>