Triangulum

noun Tri·an·gu·lum \ trī-ˈaŋ-gyə-ləm \

Definition of Triangulum

astronomy
: a small northern constellation that is visible between the constellations of Andromeda and Aries and that is represented by the figure of an isosceles triangle
  • Triangulum: A small constellation, its name comes from its three brightest stars, which form a long and narrow triangle.
  • —Graham HenrySouth Wales Echo20 Jan. 2012

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First Known Use of triangulum

1695

in the meaning defined above

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