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"coughing illness," 1765, from obsolete verb croup "to cry hoarsely, croak" (1510s), probably echoic. This was the local name of the disease in southeastern Scotland, given wide currency by Dr. Francis Home (1719-1813) of Edinburgh in his 1765 article on it. Related: Croupy.
A pathological condition of the larynx, especially in infants and children, characterized by respiratory difficulty and a hoarse, brassy cough.
An acute infection that affects the upper and lower respiratory tracts, especially the larynx, trachea, and bronchi, and is caused most commonly by viruses of the genus Paramyxovirus. It is characterized by labored breathing and obstruction below the glottis, accompanied by a barking cough.