Mount Tsurugi in Tokushima prefecture

(linguistics, uncommon) trigrade conjugation / (informal) 3-step process

participate in / take part in / join / attend

double happiness, 囍

(mahjong) a winning hand with melds of all four wind tiles

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

(literally) one side / everywhere, all around, the whole area / one viewpoint, one opinion or way of thinking / the front page of a newspaper

for the time being, for the present

the basics, a general idea

someone else's younger sister