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EPOCH
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I. (noun)
Sense 1
Meaning:
A unit of geological time that is a subdivision of a period and is itself divided into ages
Classified under:
Nouns denoting time and temporal relations
Hypernyms ("epoch" is a kind of...):
geologic time; geological time (the time of the physical formation and development of the earth (especially prior to human history))
Instance hyponyms:
Holocene; Holocene epoch; Recent; Recent epoch (approximately the last 10,000 years)
Glacial epoch; Pleistocene; Pleistocene epoch (from two million to 11 thousand years ago; extensive glaciation of the northern hemisphere; the time of human evolution)
Pliocene; Pliocene epoch (from 13 million to 2 million years ago; growth of mountains; cooling of climate; more and larger mammals)
Miocene; Miocene epoch (from 25 million to 13 million years ago; appearance of grazing mammals)
Oligocene; Oligocene epoch (from 40 million to 25 million years ago; appearance of sabertoothed cats)
Eocene; Eocene epoch (from 58 million to 40 million years ago; presence of modern mammals)
Paleocene; Paleocene epoch (from 63 million to 58 million years ago; appearance of birds and earliest mammals)
Holonyms ("epoch" is a part of...):
geological period; period (a unit of geological time during which a system of rocks formed)
Sense 2
Meaning:
A period marked by distinctive character or reckoned from a fixed point or event
Synonyms:
epoch; era
Classified under:
Nouns denoting time and temporal relations
Hypernyms ("epoch" is a kind of...):
period; period of time; time period (an amount of time)
Hyponyms (each of the following is a kind of "epoch"):
day (an era of existence or influence)
age; historic period (an era of history having some distinctive feature)
modern era (the present or recent times)
Instance hyponyms:
Caliphate (the era of Islam's ascendancy from the death of Mohammed until the 13th century; some Moslems still maintain that the Moslem world must always have a calif as head of the community)
Christian era; Common era (the time period beginning with the supposed year of Christ's birth)
Derivation:
epochal (highly significant or important especially bringing about or marking the beginning of a new development or era)
Sense 3
Meaning:
(astronomy) an arbitrarily fixed date that is the point in time relative to which information (as coordinates of a celestial body) is recorded
Synonyms:
date of reference; epoch
Classified under:
Nouns denoting time and temporal relations
Hypernyms ("epoch" is a kind of...):
date (the particular day, month, or year (usually according to the Gregorian calendar) that an event occurred)
Domain category:
astronomy; uranology (the branch of physics that studies celestial bodies and the universe as a whole)
Context examples:
An epoch of the early Tertiary period, found in-between the Oligocene and the Pliocene eras.
(Miocene epoch, NOAA Paleoclimate Glossary)
A coded value specifying the kind of epoch.
(Epoch Type Code, NCI Thesaurus)
An integer specifying the relative sequential or temporal ordering of this epoch among other similar epochs in a study.
(Epoch Sequence Number, NCI Thesaurus)
EXAMPLE(S): In a Study that has Screening, Treatment and Follow-Up epochs, the sequence number indicates which Epoch precedes the other.
(Epoch Sequence Number, NCI Thesaurus/BRIDG)
Even though the merger took place at a very remote epoch, the stars in the Sausage galaxy can be picked out today.
(The Gaia Sausage: the major collision that changed the Milky Way, University of Cambridge)
Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed.
(Final Descent Image from Rosetta Spacecraft, NASA)
The maturity of the stars seen in MACS1149-JD1 raises the question of when the very first galaxies emerged from total darkness, an epoch astronomers romantically term “cosmic dawn”.
(ALMA and VLT Find Evidence for Stars Forming Just 250 Million Years After Big Bang, ESO)
Scientists refer to this as the "epoch of reionization."
(First Stars Formed Later Than We Thought, NASA)
Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed.
(Rosetta closing in on comet, NASA)
By this, no doubt, both ape-men and Indians had at different epochs reached the top, and Maple White with his companion had taken the same way.
(The Lost World, by Sir Arthur Conan Doyle)
