extraordinary

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Beyond what is ordinary or usual: extraordinary authority.
2. adj. Highly exceptional; remarkable: an extraordinary achievement.
3. adj. Employed or used for a special service, function, or occasion: a minister extraordinary; an extraordinary professor.

Century Dictionary and Cyclopedia

1. Being beyond or out of the common order or rule; not of the usual, customary, or regular kind; not ordinary: as, extraordinary evils require extraordinary remedies.
2. Not pertaining to a regular system or sequence; exceptional; special: as, an extraordinary courier or messenger; an ambassador extraordinary; the extraordinary jurisdiction of a court; a gazette extraordinary.
3. In universities, relating to studies outside of the regular curriculum, or to lectures not recognized by the university as of the first rank of importance. In the middle ages ordinary lectures were so called because their subjects, forms, times, and places were fixed by the faculty or nation, while those of the extraordinary lectures were within certain limits left to the will of the lecturer. The extraordinary lectures could only be given at times not occupied by ordinary lectures. They treated of every subject except logic, theology, law, and medicine.
4. Exceeding the common degree or measure; hence, remarkable; uncommon; rare; wonderful: as, the extraordinary genius of Shakspere; an edifice of extraordinary grandeur.
5. Synonyms Unusual, singular, extra, unwonted, signal, egregious, marvelous, prodigious, strange, preposterous.
6. n. Anything uncommon or unusual; a thing exceeding the usual order, practice, or method.
7. n. An express messenger or courier.
8. n. Extra expense or indulgence.
9. n. In the British service, an allowance to troops beyond the gross pay, such as the expenses for barracks, encampments, etc.
10. Remarkably; exceptionally; extraordinarily.

Wiktionary

1. adj. Not ordinary; exceptional; unusual;

GNU Webster's 1913

1. adj. Beyond or out of the common order or method; not usual, customary, regular, or ordinary
2. adj. Exceeding the common degree, measure. or condition; hence, remarkable; uncommon; rare; wonderful.
3. adj. Employed or sent upon an unusual or special service.
4. n. That which is extraordinary; -- used especially in the plural.

WordNet 3.0

1. adj. far more than usual or expected
2. adj. beyond what is ordinary or usual; highly unusual or exceptional or remarkable
3. adj. (of an official) serving an unusual or special function in addition to those of the regular officials