時制 is read as じせい (jisei) and means tense.
じせい
jisei
にじゅうよじかんせい
around-the-clock system
ていじせい
part time (school system)
じかかいけいせいど
mark-to-market accounting system
じせいのいっち
sequence of tenses
せんじへんせい
war organization
へいじへんせい
peace organization
せんじきんせいひん
contraband of war
ときおり
sometimes
じかんわり
timetable (esp. a weekly school timetable)
じき
time
じそく
speed (per hour)
じげん
(school) period