‘三刻’ literally means ‘three ke,’ where ‘ke’ (刻) is a traditional Chinese unit of time equal to 15 minutes. Thus, ‘三刻’ equals 45 minutes — three quarters of an hour. The character 三 (sān) means ‘three,’ and 刻 (kè) originally referred to a ‘mark’ or ‘notch’ on a water clock, later standardized as a 15-minute interval. Though largely replaced by the modern minute-based system in daily life, ‘三刻’ still appears in formal announcements, historical contexts, or poetic expressions to convey precise yet elegant time references.

This term is rarely used in casual speech — native speakers typically say ‘四十五分钟’ (45 minutes) or ‘三个刻钟’ in spoken Mandarin. However, it may appear in radio broadcasts, train schedules, or literary works to evoke tradition or formality. It functions strictly as a noun denoting duration, not as a modifier before nouns (e.g., you cannot say *三刻钟会议); instead, use ‘三刻钟’ for clarity in modern usage.