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八角形 (hakkakukei) Japanese meaning: octagon | Kotomora

八はっ角かく形けい

は

っ

か

く

け

い

Meanings

1

Geometric term for an eight-sided polygon. The reading はっかっけい is a common variant.

この建たて物ものは八はっ角かく形けいの形かたち

を

し

て

いる

。

This building has an octagonal shape.

八はっ角かく形けいの内ない角かくの和わは1080度どです。

The sum of the interior angles of an octagon is 1080 degrees.

Kanji

八eight, eight radical (no. 12)
角angle, corner, square
形shape, form, style

Related words

六ろっ角かく形けい
Hexagon (six-sided polygon).
五ご角かく形けい
Pentagon (five-sided polygon).

Built from

八はっ角かく+形けい

Written forms

八角形
- はっかくけい
  Standard kanji spelling for 'octagon'.
- はっかっけい
はっかっけい

Etymology

Formed from 八 and 角形 “polygonal shape.” 八 changes from はち to はっ before か through促音化, yielding はっかくけい.