Apollo

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

• noun Greek Mythology The god of prophecy, music, medicine, and poetry, sometimes identified with the sun.
• noun A young man of great physical beauty.

from The Century Dictionary.

• noun In Greek and later in Roman mythology, one of the great Olympian gods, the son of Zeus (Jupiter) and Leto (Latona), representing the light- and life-giving influence, as well as the deadly power, of the sun, and often identified with the sun-god, Helios.
• noun [lowercase] In entomology, a butterfly, Papilio apollo.

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

• noun (Classic Myth.) A deity among the Greeks and Romans. He was the god of light and day (the “sun god”), of archery, prophecy, medicine, poetry, and music, etc., and was represented as the model of manly grace and beauty; -- called also Phébus.
• noun a celebrated statue of Apollo in the Belvedere gallery of the Vatican palace at Rome, esteemed of the noblest representations of the human frame.

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

• noun astronomy An asteroid possessing an orbit that crosses the orbit of the Earth and an orbital period of over one year, with semimajor axes greater than 1 AU, and perihelion distances less than 1.017 AU.
• proper noun astronomy The planet Mercury, when observed as a Morning Star.
• proper noun A United States space program, and the vehicles it created, used for human travel to the moon.
• proper noun with “the” Apollo Theater, a music hall in New York City associated with African-American performers.
• proper noun A butterfly (Parnassius apollo, a large swallowtail with black and red spots on white wings).
• proper noun A male given name.
• proper noun A placename.

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

• noun (Greek mythology) Greek god of light; god of prophecy and poetry and music and healing; son of Zeus and Leto; twin brother of Artemis