n. (astronomy) an arbitrarily fixed date that is the point in time relative to which information (as coordinates of a celestial body) is recorded
n. a unit of geological time that is a subdivision of a period and is itself divided into ages
词态变化
复数形式:epochs
常见例句
1
An inscription in which certain numeral letters, made to appear specially conspicuous, on being added together, express a particular date or epoch, as in the motto of a medal struck by Gustavus Adolphus in 1632: ChrIstVs DVX
2
It becomes ep-before a vowel, as in epoch, and eph-before a Greek aspirate, as in ephemeral.
3
A work of art or of human industry, of an early epoch; especially, a book printed before a
4
the study of the geography of ancient times or ancient epochs
5
a member of the Paleo-American peoples who were the earliest human inhabitants of North America and South America during the late Pleistocene epoch
