ten o'clock

ten o'clock (uncountable)

1. (In both the 12-hour clock and the 24-hour clock) The start of the eleventh hour of the day; 10:00 a.m. (10:00).

   The morning coffee break starts at ten o'clock (= "The morning coffee break starts at 10:00 a.m.").

2. (Only in the 12-hour clock) The start of the twenty-third hour of the day; 10:00 p.m. (22:00).

   Supper service ends at ten o'clock (= "Supper service ends at 10:00 p.m.").

3. (informal) A position to the left and slightly ahead (horizontal clock orientation) (from the location of the 10 mark on a clock face)

   We've got a bogey at ten o'clock.