The state of being distended, enlarged, swollen from internal pressure. For example, on inhalation there is distention of the lungs due to the increased air pressure within the lungs. The word "distention" comes from a Latin root "tendere," to extend. The word "tendon" comes from the same root.
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dis·ten·tion (dis-tenґshən) the state of being distended or enlarged; the act of distending.