“Top of the hour” means “on the hour” or the hour exactly. “Bottom of the hour” isn’t as common, but yes, you got it right: the half hour. Think of a clock: at 00, the minute hand is pointing to the top of the clock. At :30, the minute hand is pointing to the bottom of the clock.Click to see full answer. Simply so, what does it mean by top of the hour?top of the hour. the beginning of any or each of the twenty-four divisions of the day; noon, 1:00, 2:00, etc.: news is broadcast at the top of the hour. Origin of top of the hour. in reference, refer to the position of the minute hand on the numeral “12” at the top of a clock face. what is the bottom half of the hour? Noun. The time at (or very close to) half the next hour of time. “At Seven o’clock, He said to get in touch with him again at the bottom of the hour, so I called him back at seven thirty.” Just so, what does bottom of hour mean? The time at (very close to) half the next hour of time. Refers to the position of the long hand on a clock face. He said to get in touch with him again at the bottom of the hour.What does it mean to be at the bottom?at bottom. phrase. You use at bottom to emphasize that you are stating what you think is the real nature of something or the real truth about a situation. [emphasis]