horo-, hour- +

Occurring every two hours.

1. A demand, as by applause, for a repetition of a song, act, etc., or for a performance of a number or piece additional to those on a program, or for a reappearance by the performers, as at the end of a concert, recital, etc.
2. Used to demand an additional or repeated performance of something.
3. Etymology: used in the sense "again" from French, "again, still, yet"; said to be possibly from Latin hanc ad horam, "to this hour".

Writing about time and timekeeping instruments.

Any device used to tell the time; such as, a clock or sundial.

Of or pertaining to horology, or referring to time-keeping devices; such as, clocks and sundials.

1. A description of horologes or timepieces.
2. The art of constructing horologes.

1. Someone who studies the science of measuring time.
2. Someone skilled in making clocks and watches.

1. The science of measuring time.
2. The art of making timekeeping instruments.

An instrument for measuring time.

The measurement of time; also, the determination of the exact error of a timepiece by observation.

1. The aspect of the planets and stars at a given moment, as the moment of a person's birth, used in astrology.
2. An astrologer's description of an individual's personality and future based on the position of the planets in relation to the sign of the zodiac under which the person was born.
3. A diagram of the heavens, showing the relative position of planets and the signs of the zodiac, for use in calculating births, foretelling events in a person's life, etc.
4. A prediction of future events or advice for future behavior based on the diagram described in the previous definition.

1. The making and interpretation of horoscopes.
2. The casting or taking of horoscopes.

Of or pertaining to evolution at a rate standard for a given group of plants or animals.

1. One of the 24 equal parts of a day.
2. One of the points on a timepiece marking off 12 or 24 successive intervals of 60 minutes, from midnight to noon and noon to midnight or from midnight to midnight.
3. The time of day as indicated by a 12-hour clock and the time of day determined on a 24-hour basis: 1730 hours is 5:30 p.m.
4. A unit of measure of longitude or right ascension, equal to 15° or 1/24 of a great circle.
5. A customary or fixed time; such as, "the dinner hour".
6. Etymology: from Old French hore, "one-twelfth of a day" (sunrise to sunset), from Latin hora, "hour, time, season"; from Greek hora. "any limited time"; referring to a day, hour, season, and year.

The Greeks borrowed the notion of dividing the day into hours from the Babylonians, but the Babylonian hour was one-twelfth of the whole day and therfore twice as long as a modern hour. The Greeks divided only the period of light into 12 parts, and the Romans adopted the system from them.

Night was not similarly divided until much later, and so the period of time covered by an hour varied according to the season.

In the 16th century, a distinction was sometimes made between temporary (unequal) hours and sidereal (equal) ones.

1. An instrument for measuring time, consisting of two glass chambers connected by a narrow neck and containing a quantity of sand, mercury, or another flowing substance that trickles from the upper chamber to the lower in a fixed amount of time, often one hour.
2. An hourglass-shaped computer icon that shows that a task is being performed but is not yet completed.