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一等星 (いっとうせい) Japanese meaning | Kotomora

一いっ等とう星せい

い

っ

と

う

せ

い

Meanings

1

noun

first magnitude star

astronomy

Astronomical term for the brightest class of stars visible to the naked eye. Often used in stargazing or educational contexts.

今こん夜やは一いっ等とう星せいがよく見みえる。
Tonight, the first magnitude stars are clearly visible.
シリウスは一いっ等とう星せいの中なか

で

最もっと

も

明あか

るい

。

Sirius is the brightest among the first magnitude stars.

Written forms

一いっ等とう星せい
Standard kanji spelling for 'first magnitude star'.
１いっ等とう星せい
Numerical variant; common in technical or abbreviated contexts.

Kanji

一one, one radical (no.1)
等etc., and so forth, class (first)
星star, spot, dot

Similar words

恒こう星せい
恒星 is a general term for 'fixed star', while 一等星 specifically refers to stars of the first magnitude.
等とう級きゅう
等級 means 'magnitude' or 'grade' in astronomy; 一等星 is a compound using this concept.

Etymology

Compound of 一等 (first class) and 星 (star), directly describing the brightest category of stars in the magnitude system.