Croupous \Croup"ous\ (kr??p"?s), a. (Med.) Relating to or resembling croup; especially, attended with the formation of a deposit or membrane like that found in membranous croup; as, croupous laryngitis.

Croupous pneumonia, pneumonia attended with deposition of fibrinous matter in the air vesicles of the lungs; ordinary acute pneumonia.

Source: Webster's Revised Unabridged Dictionary (1913)