1A character used mainly in compounds and as a suffix, with two main threads: (1) a system or scheme (会員制 'membership-based', 予約制 'reservation-based', 週休二日制 'five-day workweek system'); and (2) to control, regulate, or restrain (制する, 抑制, 強制). Rarely used on its own — chiefly as 〜制 or within compounds. An archaic sense is 'imperial command / decree'.
このレストランは完全予約制です。
This restaurant is fully reservation-based.
当クラブは会員制で、入会には紹介が必要だ。
This club is membership-based; joining requires an introduction.
来年から週休二日制が導入される。
A two-days-off-per-week system will be introduced from next year.
怒りを感じても、感情を制することが大切だ。
Even when you feel anger, it's important to keep your emotions in check.