or·di·nar·y 
(ôrdn-ĕr′ē)
(ôrdn-ĕr′ē)adj.
1. Commonly encountered; usual: an ordinary delay at the bridge tolls. See Synonyms at common.
2.
a. Having no special ability, quality, or purpose: ordinary people; ordinary black tea.
b. Not particularly good; not better than average: The service was good, but the food was very ordinary.
3. Law Having direct authority to decide a case, rather than being delegated that power, as a judge.
4. Mathematics Designating a differential equation containing no more than one independent variable.
n. pl. or·di·nar·ies
1. The usual or normal condition or course of events: Nothing out of the ordinary occurred.
2. Law A judge with direct authority as opposed to delegated authority to decide a case.
3. often Ordinary Ecclesiastical
a. The parts of the Mass that remain unchanged from day to day.
b. A division of the Roman Breviary containing the unchangeable parts of the office other than the Psalms.
c. A cleric, such as the residential bishop of a diocese, with ordinary jurisdiction over a specified territory.
4. Heraldry One of the simplest and commonest charges, such as the bend and the cross.
5. Chiefly British
a. A complete meal provided at a fixed price.
b. A tavern or inn providing such a meal.
[Middle English ordinarie, from Old French, from Latin ōrdinārius, from ōrdō, ōrdin-, order; see ar- in the Appendix of Indo-European roots.]
or′di·nari·ness n.