sultan

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A ruler of a Muslim country, especially of the former Ottoman Empire.
• noun A powerful person.

from The Century Dictionary.

• noun A Mohammedan sovereign: as, the Sultan of Zanzibar or of Morocco; by way of eminence, the ruler of Turkey, who assumes the title of Sultan of sultans; in old use, any ruler.
• noun In ornithology, a purple or hyacinthine gallinule, or porphyrio; a bird of either of the genera Porphyrio and Ionornis, belonging to the rail family, Rallidæ: so called from their gorgeous coloration. The American sultan is Ionornis martinica. See the generic names, and gallinule. Also called sultana.
• noun An ornamental variety of the domestic hen, of small size and pure-white plumage, and having the head heavily crested and bearded, beak white, legs blue, shanks feathered, and toes five.
• noun Either of two garden-flowers, Centaurea moschata, the sweet sultan, with purple or white flowers, and C. suaveolens, the yellow sultan: both often classed as Amberboa.

from the GNU version of the Collaborative International Dictionary of English.

• noun A ruler, or sovereign, of a Mohammedan state; specifically, the ruler of the Turks; the Padishah, or Grand Seignior; -- officially so called.
• noun (Bot.) See Sweet sultan, under Sweet.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Originally, a secular office, formally subordinate to -, but de facto the power behind the throne of the (theoretically universal) caliph.
• noun A hereditary ruler in various Muslim states (sultanate), varying from petty principalities (as in Indonesia and in Yemen), often vassal of a greater ruler, to independent realms, such as Oman, Brunei, or an empire such as the Turkish Ottoman Empire.
• noun A variant of solitaire, played with two decks of cards.
• noun A breed of chicken originating in Turkey, kept primarily in gardens for ornamental reasons. See: sultan (chicken)

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the ruler of a Muslim country (especially of the former Ottoman Empire)