This is the 9421st most frequent Russian word.
треугольник
Triangle.
In this sentence, 'треугольник' refers to the geometric shape known as a triangle.
Треугольник имеет три стороны.
The triangle has three sides.
Here, 'треугольник' describes the musical instrument triangle, often made of metal and used in orchestras.
Этот музыкальный инструмент треугольник издает приятный звук.
This musical instrument called a triangle produces a pleasant sound.
In this context, 'треугольник' is used metaphorically to describe a situation involving three people intertwined in a romantic relationship.