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3 o'clock
afternoon snack (eaten around 3 o'clock)
three ages of Buddhism (following the death of Gautama Buddha; age of the true law, age of the copied law, and age of the degeneration of the law); three ages of the dharma
三時のおやつにケーキを食べた。
I had cake for a three o'clock snack.
授業は三時に終わる予定だ。
The class is scheduled to end at three o'clock.
今日は三時から歯医者の予約がある。
I have a dentist appointment from three o'clock today.