whoo /wuː/exclamation 3noun 1verb 1forms 3 exclamation3 •a shout showing that the speaker is very happy and excited •The cry of an owl. •The wailing of a ghost."You are mistaken; I am a ghost; whoo!" said I, choking back my rage. — 1949 noun1 •A "whoo" sound; the cry of an owl or similar. verb1 •To make a whoo sound, of delight, whistling, or of an owl etc. formswhooed · whooing · whoos