croup n.

"coughing illness," a name given to various diseases involving interference at the glottis with respiration," 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 treatise on it. Related: Croupy.