one day

the third day of the month / three days

the tenth day of the month / ten days

(rare) the first day of the month

(rare) a birthday

a birthday

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

thirty-first day of the month

all day

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