Synonym of 地動説 (chidōsetsu, “heliocentrism”)

a birthday

one day, 24 hours / the daytime, the period from dawn until dusk / (figuratively) a short period of time / one day, someday, an unspecified day / the first day of the month

regular day off (e.g. closed every Monday)

the twentieth day of the month / twenty days / Short for 二十日鼠 (hatsuka nezumi): a house mouse

(physics) strong interaction

幾日も幾日も: day after day

the due date / the expiration date (of the term)

the last day of the year, New Year's Eve

(collective, chiefly attributive) Japan and China