croup /kɹuːp/noun 2verb 1forms 3 noun2 •An infectious illness of the larynx, especially in young children, causing respiratory difficulty. •The top of the rump of a horse or other quadruped.So light to the croup the fair lady he swung, / So light to the saddle before her he sprung. — 1808 verb1 •(dialect, no longer used) To croak, make a hoarse noise. formscrouped · crouping · croups