noun (1)
mo·​noc·​er·​os | \ mə-ˈnä-sə-rəs How to pronounce monoceros (audio) \
plural -es

Definition of monoceros

 (Entry 1 of 2)

1 obsolete : one-horned rhinoceros
2 : a fish (as the swordfish or sawfish) with one hornlike process


noun (2)
Mo·​noc·​er·​os | \ mə-ˈnä-sə-rəs How to pronounce Monoceros (audio) \

Definition of Monoceros (Entry 2 of 2)

: 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

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First Known Use of monoceros

Noun (2)

1715, in the meaning defined above

History and Etymology for monoceros

Noun (1)

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

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The first known use of monoceros was in 1715

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Cite this Entry

“Monoceros.” Dictionary, Merriam-Webster, Accessed 25 Jan. 2022.

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