Pisces

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A constellation in the equatorial region of the Northern Hemisphere near Aries and Pegasus. Also called Fishes.
2. n. The 12th sign of the zodiac in astrology. Also called Fishes.
3. n. One who is born under this sign.

Century Dictionary and Cyclopedia

1. A constellation and sign of the zodiac; the Fishes. The figure represents two fishes united by a ribbon attached to their tails. One of the fishes is east, the other south, of the square of Pegasus.
2. In zoology, a class of vertebrates, the fishes, to which different limits have been assigned. See fish.

Wiktionary

1. n. astronomy A constellation of the zodiac supposedly shaped like a pair of fish.
2. n. astrology The zodiac sign for the fish, ruled by Neptune and covering February 20 - March 20 (tropical astrology) or March 15 - April 14 (sidereal astrology).
3. n. Someone with a Pisces star sign

GNU Webster's 1913

1. n. The twelfth sign of the zodiac, marked ♓ in almanacs.
2. n. A zodiacal constellation, including the first point of Aries, which is the vernal equinoctial point; the Fish.
3. n. (Zoöl.) The class of Vertebrata that includes the fishes. The principal divisions are Elasmobranchii, Ganoidei, and Teleostei.

WordNet 3.0

1. n. a large faint zodiacal constellation; between Aquarius and Aries
2. n. the twelfth sign of the zodiac; the sun is in this sign from about February 19 to March 20
3. n. a group of vertebrates comprising both cartilaginous and bony fishes and sometimes including the jawless vertebrates; not used technically
4. n. (astrology) a person who is born while the sun is in Pisces