Definition of Hydrus

: a small southern constellation that is visible between the constellations of Tucana and Mensa and that is represented by the figure of a snake … a small constellation in the southern sky called Hydrus, which means “male water snake.”— Jesse Eisinger and Jake Bernstein, Knoxville (Tennessee) News-Sentinel, 18 Apr. 2010

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First Known Use of Hydrus

1675, in the meaning defined above

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The first known use of Hydrus was in 1675

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Cite this Entry

“Hydrus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hydrus. Accessed 20 Sep. 2020.

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