零時(れいじ) れいじ noun midnight; zero o'clock time-general 1. midnight; zero o'clock; 12:00 AM The point in time at exactly 0:00, the start of a new day. Used in formal time-telling and schedules. 零時(れいじ)を過(す)ぎた。🔊 It's past midnight. 零時(れいじ)ちょうどに新年(しんねん)のカウントダウンが始(はじ)まる。🔊 The New Year's countdown begins at exactly midnight. セールは零時(れいじ)から開始(かいし)されるので、夜更(よふ)かしして待(ま)っていた。🔊 The sale starts at midnight, so I stayed up late waiting. UsageUsed in formal contexts, schedules, and when specifying exact times. In casual speech, 夜中(よなか)の十二時(じゅうにじ) (12 o'clock at night) is more common.Related words午前零時(ごぜんれいじ) (0:00 AM — formal/official)正午(しょうご) (noon — 12:00 PM)深夜(しんや) (late at night — less precise than 零時(れいじ))Common collocations零時(れいじ)を回(まわ)る (to pass midnight)午前(ごぜん)零時(れいじ) (12:00 AM)零時(れいじ)過(す)ぎ (just after midnight) Related Words Compare: 正午(しょうご) (noon) Related: 深夜(しんや) (late at night) general Added 2026.3.17 9:13 · Revised 2026.10.4 15:51 17000/17204_reiji