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正三角形 (せいさんかくけい) Japanese meaning | Kotomora

正せい三さん角かく形けい

also: せいさんかっけい

せ

い

さ

ん

か

く

け

い

Freq.FrequencyTop 100,000

Meanings

1

noun

equilateral triangle; regular triangle

geometry

Geometry term for a triangle with three equal sides and angles.

正せい三さん角かく形けいの内ない角かくはすべて60度どです。
All interior angles of an equilateral triangle are 60 degrees.
この図ず形けいは正せい三

さん

角かく

形けい

です

か

？

Is this shape an equilateral triangle?

Written forms

正三角形
- せいさんかくけい
  Standard kanji spelling for 'equilateral triangle'.
- せいさんかっけい
せいさんかっけい
Common colloquial pronunciation with gemination; often written in kana when this reading is intended.

Kanji

正correct, justice, righteous
三three
角angle, corner, square
形shape, form, style

Similar words

二に等とう辺へん三さん角かく形けい
An isosceles triangle has two equal sides, while a 正三角形 has all three sides equal.
直ちょっ角かく三さん角かく形けい
A right triangle has one 90-degree angle; a 正三角形 has all angles equal to 60 degrees.

Etymology

Compound of 正 (sei, 'regular, correct') + 三角形 (sankakukei, 'triangle').