Definition of o'clock
1 : according to the clock the time is three o'clock
2 —used for indicating position or direction as if on a clock dial that is oriented vertically or horizontally an airplane approaching at six o'clock
Origin and Etymology of o'clock
contraction of of the clock
First Known Use: 1535See Words from the same year
O'CLOCK Defined for English Language Learners
Definition of o'clock for English Language Learners
: according to the clock
O'CLOCK Defined for Kids
Definition of o'clock for Students
: according to the clock The time is one o'clock.
Seen and Heard
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