Emily Dickinson Lexicon

CROUP, n.² [Scot. croup, crope, crupe, crowp, to croak, to cry or speak with a hoarse voice; Goth. hropyan; Sax. hreopan, to call out.]

The disease called technically cynanche trachealis, an inflammatory affection of the trachea, accompanied with a hoarse cough and difficult respiration. It is vulgarly called rattles.