from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A constellation near Canis Major and Canis Minor.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- proper n. A winter constellation of the northern sky, said to resemble a unicorn. It lies amid the Milky Way, just east of the constellation Orion.
from the GNU version of the Collaborative International Dictionary of English
- n. A one-horned creature; a unicorn; a sea monster with one horn.
- n. The Unicorn, a constellation situated to the east Orion.
from The Century Dictionary and Cyclopedia
- n. A unicorn, or some other one-horned animal, real or imaginary.
- n. [capitalized] A constellation, the Unicorn, south of the Twins and the Crab, and between the two Dogs, introduced by Jacob Bartsch in 1624.
- n. The narwhal, Monodon monoceros.
- n. [capitalized] In zoology:
- n. A genus of prosobranchiates of the family Muricidæ, so called from the large spine on the outer lip; the unicorn-shells. There are several species from the west coast of America.
- n. A genus of balistoid fishes.
Middle English, unicorn, from Old French, from Latin monocerōs, from Greek monokerōs, having one horn : mono-, mono- + keras, horn; see ker-1 in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
First recorded by the astronomer Jakob Bartsch in 1624, but possibly created earlier by Petrus Plancius. From Latin monoceros, a "unicorn" (Wiktionary)