Parenthesized Ideograph Sun

㈰ means Sunday in Japanese calendars. It is the one-character form of (日), usually written after a date; the weekday cycle moved from court astrology into everyday scheduling.

Text symbol

What ㈰ means

㈰ marks Sunday in Japanese date notation. It follows a date in compact form. The seven-day planetary week (days linked to heavenly bodies) reached Japan through Chinese Buddhist calendar texts and was available to court calendar makers by the end of the ninth century. The diary of court noble Fujiwara no Michinaga records continuous weekday notation in 998–1021. The cycle served astrology and divination before calendar changes in 1873 and 1876 shifted weekday marks toward everyday scheduling. – mark Monday through Saturday.

Don't confuse it with

㊐

Circled ideograph Sun

㈰ vs ㊐: both label Sunday; ㊐ encloses 日 in a circle.

(日) ㈰ vs (日): Unicode compatibility normalization (text standardization) can expand ㈰ into (日); it still marks Sunday.

Questions people ask

Why does ㈰ show as a box on some devices?

Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.