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black triangle

1. An unidentified flying object (popularly known as a UFO) in the shape of a dark triangle, typically with points of light in each corner. I know you think I'm crazy, but every spring, I see those black triangles appearing over my corn fields at night!
2. In Nazi Germany, a badge assigned to concentration camp inmates considered "asocial" or mentally unfit for work. Her clinical depression, which was vilified by the Nazis, meant she had to wear a black triangle in the concentration camp.
See also: black, triangle

eternal triangle

A sexual encounter or relationship between three people. Although exciting at first, the eternal triangle caused their relationship to suffer and ultimately end.
See also: eternal, triangle

(the) eternal triangle

a sexual or emotional relationship involving two women and one man or two men and one woman. (*Typically, a couple [man and woman] and another man or woman.) Henry can't choose between his wife and his mistress. It's the eternal triangle. I'm surprised Jane doesn't get tired of the eternal triangle. She goes out with Peter at the weekend and Jim during the week.
See also: eternal, triangle

eternal triangle

A relationship involving three lovers, such as two women involved with one man or two men with one woman. For example, The plot of the murder mystery revolved around the eternal triangle of a husband, wife, and another woman . [c. 1900]
See also: eternal, triangle

eternal triangle

a relationship between three people, typically a couple and the lover of one of them, involving sexual rivalry.
See also: eternal, triangle

eternal triangle, the

A threesome of lovers, either two men involved with or vying for one woman or two women and one man. “Eternal” here simply means that this situation has occurred over and over through the ages. The term has been traced to a book review appearing in the London Daily Chronicle in 1907, describing a novel that “deals with the eternal triangle, which, in this case, consists of two men and one woman.”
See also: eternal
References in periodicals archive ?
Pat then asked the class if anyone made a triangle with sides of 1, 1 and 18 matchsticks.
We have managed to find seven triangles with six lines but then get a bit stuck .
Triangles are among the most reliable of the continuation patterns.
Your students can attempt to derive this result by using any altitude of the triangle plus Pythagoras' theorem together with expanding backwards from Heron's result.
Applying the construction to DEF will result in a third triangle GHI, whose corresponding sides will have a difference of squares of:
If you were to continue the process by endlessly adding smaller and smaller triangles to every new side, you would produce a fractal object that mathematicians call the von Koch snowflake curve, named after a Swedish mathematician, Niels Fabian Helge von Koch.
A field of triangles crumples and twists into a wavy crystalline sea.
Pengelly (1999), suggests that commercial sets of shapes tend to promote only one type of triangle and unless children "experience a comprehensive collections of triangles of various sizes and shapes, they may think that all triangles resemble the proportions of those that are equilateral" (Pengelly, 1991, p.
As a result of those efforts the first phase of Triangle Court, Triangle I, was built in 1998 with financing from the HDC and CPC.
Also note that whenever a triangle not on the cycle contains both the in-vertex and out-vertex of a triangle that is on the cycle, we can "swap" this triangle with the other triangle by removing the other triangle from the cycle and inserting the new triangle in its place, as illustrated in Fig.
In particular, we may ask how The Law of Cosines can be expressed for the triangle located in the plane by the three points [P.
I decided to focus on the triangle, one of the geometric shapes discussed by Clements and Sarama.
The cloth panels were linked in a winding chain; Mirra stitched along one, two, or three edges of each triangle, rendering the whole assemblage a continuous meander of triangle groups in various configurations.
Software developers usually create low triangle count models so that their games can run well on low-end PCs, which make up the vast majority of products used today by consumers.