Tri·​an·​gu·​lum | \ trī-ˈaŋ-gyə-ləm How to pronounce Triangulum (audio) \

Definition of Triangulum

: 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 Henry, South Wales Echo, 20 Jan. 2012

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

First Known Use of Triangulum

1695, in the meaning defined above

Keep scrolling for more

Learn More about Triangulum

Statistics for Triangulum

Look-up Popularity

Time Traveler for Triangulum

The first known use of Triangulum was in 1695

See more words from the same year

Comments on Triangulum

What made you want to look up Triangulum? Please tell us where you read or heard it (including the quote, if possible).


tired or exhausted

Get Word of the Day daily email!

Test Your Vocabulary

Where in the World? A Quiz

  • peter bruegel tower of babel painting
  • What language does pajama come from?
Spell It

Can you spell these 10 commonly misspelled words?

Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!