triangular
adjective
tri·an·gu·lar trī-ˈaŋ-gyə-lər 
1
a
: of, relating to, or having the form of a triangle
a triangular plot of land
b
: having a triangular base or principal surface
a triangular table
a triangular pyramid
2
a(1)
: of, relating to, or involving three elements
a triangular agreement
(2)
of a military group : based primarily on three units
b
: of or relating to a love triangle
triangularity
(ˌ)trī-ˌaŋ-gyə-ˈler-ə-tē
noun -ˈla-rə-tē
triangularly
trī-ˈaŋ-gyə-lər-lē
adverb 
Example Sentences
Recent Examples on the Web With a futuristic silhouette set on a one-inch platform, Prada's pull-on rain boots are an elevated take on timeless black galoshes, complete with the label's signature triangular logo and wavy textured sole. 
Laura Lajiness Kaupke, Harper's BAZAAR, 26 July 2022 Four massive columns support the triangular front pediment (gable), and large windows let in plenty of light. Washington Post, 5 Nov. 2021 There’s a roundish globe, a more triangular bulb, and an oval shape. WIRED, 5 Sep. 2022 The story starts out on familiar lines, involving a married couple where suddenly the ex-husband of the wife appears, potentially setting up the melodrama of a triangular relationship. Patrick Frater, Variety, 1 Sep. 2022 Great for tackling big spills quickly, the mop’s triangular head can easily clean, be dunked and wrung out in the bucket, and used again in quick succession. Maya Polton, Better Homes & Gardens, 1 Sep. 2022 Noiranca’s triangular Grace Mini is one such find, made from vegan leather and designed to be worn cross-body or hand-held (peep the adorable top handle). Lauren Puckett-pope, ELLE, 1 Sep. 2022 These numbers should be familiar to anyone who’s ever studied Pascal’s triangle, a triangular arrangement of numbers that, at its simplest, is created by adding together the numbers above it, starting with 1 at the top. Steven Strogatz, Quanta Magazine, 31 Aug. 2022 Later that same day, Thompson attended a cocktail party with Variety dressed as the anti-ballerina in a frilly black tulle midi skirt, black blazer with ruffled sleeves, and a black triangular bra. Chelsey Sanchez, Harper's BAZAAR, 31 Aug. 2022 See More
Laura Lajiness Kaupke, Harper's BAZAAR, 26 July 2022 Four massive columns support the triangular front pediment (gable), and large windows let in plenty of light. Washington Post, 5 Nov. 2021 There’s a roundish globe, a more triangular bulb, and an oval shape. WIRED, 5 Sep. 2022 The story starts out on familiar lines, involving a married couple where suddenly the ex-husband of the wife appears, potentially setting up the melodrama of a triangular relationship. Patrick Frater, Variety, 1 Sep. 2022 Great for tackling big spills quickly, the mop’s triangular head can easily clean, be dunked and wrung out in the bucket, and used again in quick succession. Maya Polton, Better Homes & Gardens, 1 Sep. 2022 Noiranca’s triangular Grace Mini is one such find, made from vegan leather and designed to be worn cross-body or hand-held (peep the adorable top handle). Lauren Puckett-pope, ELLE, 1 Sep. 2022 These numbers should be familiar to anyone who’s ever studied Pascal’s triangle, a triangular arrangement of numbers that, at its simplest, is created by adding together the numbers above it, starting with 1 at the top. Steven Strogatz, Quanta Magazine, 31 Aug. 2022 Later that same day, Thompson attended a cocktail party with Variety dressed as the anti-ballerina in a frilly black tulle midi skirt, black blazer with ruffled sleeves, and a black triangular bra. Chelsey Sanchez, Harper's BAZAAR, 31 Aug. 2022 See More Word History
Etymology
Middle English trianguler, from Late Latin triangularis, from Latin triangulum
First Known Use
14th century, in the meaning defined at sense 1a
Phrases Containing triangular
Kids Definition
triangular
adjective
tri·an·gu·lar trī-ˈaŋ-gyə-lər
1
: having three angles, sides, or corners
a triangular sign
2
: of, relating to, or involving three parts or persons
Medical Definition
triangular
noun
tri·an·gu·lar trī-ˈaŋ-gyə-lər
: triquetral bone