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noun (1)

mo·​noc·​er·​os mə-ˈnä-sə-rəs How to pronounce monoceros (audio)
plural -es
: a fish (as the swordfish or sawfish) with one hornlike process


2 of 2

noun (2)

Mo·​noc·​er·​os mə-ˈnä-sə-rəs How to pronounce Monoceros (audio)
: a northern constellation that is visible between the constellations of Canis Minor and Canis Major and that is represented by the figure of a unicorn
Betelgeuse, Sirius and Procyon form an almost perfect equilateral triangle. Most of the constellation Monoceros lies in that triangle. Unless you're observing away from city lights, you probably won't see much with your naked eye. And, even from a dark site, faint Monoceros looks nothing like a unicorn.John Stanley, Arizona Republic, 26 Mar. 2005

Word History


Noun (1)

Middle English, from Middle French, from Latin, from Greek monokeros, from mon- + -keros (from keras horn)

First Known Use

Noun (2)

1715, in the meaning defined above

Time Traveler
The first known use of monoceros was in 1715

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Cite this Entry

“Monoceros.” Dictionary, Merriam-Webster, Accessed 1 Jun. 2023.

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