(In both the 12-hour clock and the 24-hour clock) The start of the second hour of the day; 1:00 a.m. (01:00). / (Only in the 12-hour clock) The start of the fourteenth hour of the day; 1:00 p.m. (13:00).

(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).

(In both the 12-hour clock and the 24-hour clock) The start of the seventh hour of the day; 6:00 a.m. (06:00).

(US, especially black slang, of a woman) Straight up and down, without curves, like the hands of a clock.

(In both the 12-hour clock and the 24-hour clock) The start of the eighth hour of the day; 7:00 a.m. (07:00). / (Only in the 12-hour clock) The start of the twentieth hour of the day; 7:00 p.m. (19:00).

(In both the 12-hour clock and the 24-hour clock) The start of the fourth hour of the day; 3:00 a.m. (03:00). / (Only in the 12-hour clock) The start of the sixteenth hour of the day; 3:00 p.m. (15:00).

(informal, humorous) A time of day, usually during the night or early in the morning, considered unreasonable or when one is prone to poor judgment.

(slang, humorous) The time of the first glass of wine (or alcoholic beverage) of the day.

Alternative form of four o'clock

(slang, humorous) The time of the first beer (or alcoholic beverage) of the day. / (slang, humorous) Time for a beer (the first of the day or otherwise).