D defs.my
Entry 1 sense Webster, 1913

Orthopnœa

· Or·thop·nœ·a · IPA
01 n. Specifically, a morbid condition in which respiration can be performed only in an erect posture; by extension, any difficulty of breathing.
  1. 1.
    Specifically, a morbid condition in which respiration can be performed only in an erect posture; by extension, any difficulty of breathing.(Med.)