(An). One who has an “ordinary or regular jurisdiction” in his own right, and not by deputation. thus a judge who has authority to take cognisance of causes in his own right is an ordinary. A bishop is an ordinary in his own diocese, because he has authority to take cognisance of ecclesiastical matters therein; but an archbishop is the ordinary of his province, having authority in his own right to receive appeals therein from inferior jurisdictions. The chaplain of Newgate was also called the ordinary thereof.
(An). A public dinner where each guest pays his quota; a table d'hôte.
“ `Tis almost dinner; I know they stay for you at the ordinary.” —Beaumont and Fletcher: Scornful Lady. iv. l.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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