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An epoch is a stretch of time that has a character of its own — a period of history you can point to and name. Writers use it for big human chapters (“the postwar epoch”). Scientists use it more tightly: in geology an epoch is a named slice of Earth’s past, shorter than a period; in astronomy it can be a fixed reference moment.
An epoch時代 is a stretch of time that has a character of its own是一段有自己特色的時間 — a period of history you can point to and name一段你可以指出來、並且命名的歷史時期。Writers作家 use it for big human chapters會用它來指稱人類歷史上的大篇章 ("the postwar epoch")（例如「戰後時代」）。Scientists科學家 use it more tightly用得比較嚴謹: in geology在地質學裡 an epoch is a named slice of Earth's pastepoch是地球歷史裡一個有名稱的時間切片, shorter than a period比period還短; in astronomy在天文學裡 it它 can be a fixed reference moment可以指一個固定的參考時間點。
The word feels formal. Day-to-day English more often says age, era, or period.
The word這個字 feels formal給人的感覺很正式。Day-to-day English日常英文 more often says age, era, or period比較常說age、era，或period。
Though actually, the Greek starting point was a pause, a place where something (a star, a count of time) seems to halt — then the marked stretch that follows that point. It is not the same as epic, which is a long hero story.
Though actually不過其實 the Greek starting point希臘文的起點 was a pause意思是「停頓」, a place where something (a star, a count of time) seems to halt是某個東西（一顆星、一段計時）看起來停下來的那個點 — then而 the marked stretch that follows that point之後才是那個點所標記出來的那段時間。It它 is not the same as epic跟epic不一樣, which epic指的是 is a long hero story一部很長的英雄故事。
組成From Greek epokhe, a pause or a fixed point: epi- “upon” + ekhein “to hold.” Through Medieval Latin epocha. First a point where a star seems to stop; then a marked stretch of time.
同家族的字
- epoch-making“making an epoch” — important enough to open a new stretch of time
原始詞典資料7 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
EPOCHnoun
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medicinesciencesAn intensive chemotherapy regimen for treating aggressive non-Hodgkin lymphoma, consisting of etoposide, prednisolone, Oncovin (vincristine), cyclophosphamide, and hydroxydaunorubicin.
epochnoun/ˈiːpɒk/
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A particular period of history, or of a person's life, especially one considered noteworthy or remarkable.
- I grew bitter in my words—I believed the worst of everyone; nay, I sometimes doubted the affection of my kind, my indulgent parents. But let me hastily pass over this vain and profitless epoch,—the fierce tempest, and the weary calm, were but the appointed means by which I reached the harbour of faith and rest.
- And it occasionally happens that a period in which one had, hitherto, been mainly looking for the coming to birth of new things, suddenly reveals itself as an epoch of fading and decay.
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A notable event which marks the beginning of such a period.
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astronomychronologycomputingA specific instant in time, chosen as the point of reference or zero value of a system that involves identifying instants of time.
- UNIX epoch; J2000 epoch
- Appendix A gives formulae for the calculation of the orbital elements of the planets at any time referred to the mean ecliptic and equinox of the epoch of noon on 1st January 2000; this is called the J2000 epoch.
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geographygeologynatural-sciencesA geochronologic unit of hundreds of thousands to millions of years; a subdivision of a period, and subdivided into ages (or sometimes subepochs).
- Now during the time of the glacial epoch the greatest distance of the sun in winter was 98¼ millions of miles, whereas it is now, in winter, only 91½ millions of miles, the mean distance being taken as 93 million miles.
- Phoenix and Lubbock are both caught in severe drought, and it is going to get much worse. We may see many such [dust] storms in the decades ahead, along with species extinctions, radical disturbance of ecosystems, and intensified social conflict over land and water. Welcome to the Anthropocene, the epoch when humans have become a major geological and climatic force.
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One complete presentation of the training data set to an iterative machine learning algorithm.
- The neural network was trained over 500 epochs.
- For now, let's test and evaluate our GAN by comparing the results from the first epoch with the generated images from the last epoch.
epochverb/ˈiːpɒk/
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sciencesTo divide (data) into segments by time period.
- The continuous data were epoched into segments of 1500 ms (starting 500 ms before visual stimulus onset), time-locked to stimulus onset (0 ms) and sorted according to experimental conditions.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。