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Had we been thinking of the time as marked by certain great events, or as a period in which great results were effected, we should have called the times when these events happened epochs, and the whole period an epoch. The capture of Constantinople is an epoch in the history of Mahometanism; but the flight of Mahomet is its era. Epoch meaning, definition, what is epoch: a period of history: Learn more. Space pioneer shepard smith.

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ep·och

(ĕp′ək, ē′pŏk′)n.

epoch

(ˈiːpɒk) n

ep•och

(ˈɛp ək; esp. Brit. ˈi pɒk)
n.

ep·och

(ĕp′ək, ē′pŏk′)

epoch

- Pronounced EH-puhk, it is from Greek epokhe, 'fixed point in time, stoppage,' and it was first the initial point in a chronology from which succeeding years were numbered.

epoch

Noun	1.	epoch - a period marked by distinctive character or reckoned from a fixed point or event period, period of time, time period - an amount of time; 'a time period of 30 years'; 'hastened the period of time of his recovery'; 'Picasso's blue period' day - an era of existence or influence; 'in the day of the dinosaurs'; 'in the days of the Roman Empire'; 'in the days of sailing ships'; 'he was a successful pianist in his day' historic period, age - an era of history having some distinctive feature; 'we live in a litigious age'
2.	epoch - (astronomy) an arbitrarily fixed date that is the point in time relative to which information (as coordinates of a celestial body) is recorded astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole date - the particular day, month, or year (usually according to the Gregorian calendar) that an event occurred; 'he tried to memorizes all the dates for his history class'
3.	epoch - a unit of geological time that is a subdivision of a period and is itself divided into ages geologic time, geological time - the time of the physical formation and development of the earth (especially prior to human history) geological period, period - a unit of geological time during which a system of rocks formed; 'ganoid fishes swarmed during the earlier geological periods'

epoch

epoch

nounA particular time notable for its distinctive characteristics:

epoch

[ˈiːpɒk]N → épocaf
to mark an epoch → hacerépoca, marcar un hito

epoch

epoch

[ˈiːpɒk]n (period) → epoca, era

epoch

(ˈiːpok) , ((American) ˈepək) noun
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Epoch

In astronomy, an epoch is a moment in time used as a reference point for some time-varying astronomical quantity, such as the celestial coordinates or elliptical orbital elements of a celestial body, because these are subject to perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or aphelion of its orbit, or the size of the major axis of its orbit.The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics can be used to generate an ephemeris, a table of values giving the positions and velocities of astronomical objects in the sky at a given time or times.Astronomical quantities can be specified in any of several ways, for example, as a polynomial function of the time-interval, with an epoch as a temporal point of origin. Alternatively, the time-varying astronomical quantity can be expressed as a constant, equal to the measure that it had at the epoch, leaving its variation over time to be specified in some other way—for example, by a table, as was common during the 17th and 18th centuries.