key (to open a lock) / the clue to a problem / key (on the keyboard of a piano etc.) / key (on the keyboard of a computer) / key (a pitch in music)

chi

a personal or private matter / selfishness / privacy, secrecy / (women's speech, obsolete) a brother-in-law

personal, private / secret

(formal) first-person singular pronoun: I, me

(polite) first-person singular pronoun: I, me

a personal or private matter / (by extension) selfishness

private; mine

Alternative spelling of 私達 (“we; us”)

(computing) shift key (key on a personal computer or terminal keyboard)