Kyūjitai form of 通宝

Short for 定時通過 (teiji tsūka, “(rail transport) passing through a station at the exact scheduled time”).

(Internet slang) Short for 個別通話 (kobetsu tsūwa, “individual conversation (as opposed to public chatting)”).

extreme regret

to travel along a specific route / to have contact with other people, to engage in social intercourse

passage through an object / passage of a test in school / passage of a bill / passage through a screening

currency

general rule

mastery, proficiency, expertise / semenarche, first ejaculation during puberty

to be well versed (in), to have expertise, to be well acquainted (with)