<p><strong>Noun</strong></p><ul><li>Any of numerous, chiefly nocturnal birds of prey, of the order Strigiformes, having a broad head with large, forward-directed eyes that are usually surrounded by disks of modified feathers; many populations are diminishing owing to loss of habitat.</li><li>One of a breed of domestic pigeons having an owllike appearance.</li><li>Night owl.</li><li>A person of owllike solemnity or appearance.</li></ul><p><strong>Adjective</strong></p><ul><li>Operating late at night or all night: an owl train.</li></ul>