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長半径 (chouhankei) Japanese meaning: semi-major axis | Kotomora

長ちょう半はん径けい

ちょ

う

は

ん

け

い

Meanings

1

semi-major axis

Geometry term for half the longest diameter of an ellipse. Also called 半長径.

See also: 半長径

楕だ円えんの長ちょう半

はん

径けい

は

、

中ちゅう

心しん

から

最もっと

も

遠とお

い

点てん

まで

の

距きょ

離り

です

。

The semi-major axis of an ellipse is the distance from the center to the farthest point.

Kanji

長long, leader, superior
半half, middle, odd number
径diameter, path, method

Related words

半はん長ちょう径けい
Synonym for 長半径; both mean semi-major axis. 半長径 is less common.
短たん半はん径けい
Semi-minor axis, the shorter radius of an ellipse.

Word family

軌き道どう長ちょう半はん径けい
semi-major axis

Built from

長ちょう+半はん径けい

Etymology

Compound of 長 (long) + 半径 (radius). A straightforward calque of the English 'semi-major axis'.