Noun

(en noun)

A time period of indeterminate length, generally more than one year.

* {{quote-book, year=1963, author=(Margery Allingham), title=(The China Governess)

, chapter=6 citation , passage=Even in an era when individuality in dress is a cult, his clothes were noticeable. He was wearing a hard hat of the low round kind favoured by hunting men, and with it a black duffle-coat lined with white.}}

* {{quote-magazine, date=2012-01

, author=Philip E. Mirowski , title=Harms to Health from the Pursuit of Profits , volume=100, issue=1, page=87 , magazine= citation , passage=In an era when political leaders promise deliverance from decline through America’s purported preeminence in scientific research, the news that science is in deep trouble in the United States has been as unwelcome as a diagnosis of leukemia following the loss of health insurance.}}

(geology) A unit of time, smaller than .

Noun

(en noun)

A particular period of history, especially one considered remarkable or noteworthy.

*{{quote-magazine, date=2012-01

, author=Donald Worster , title=A Drier and Hotter Future , volume=100, issue=1, page=70 , magazine= citation , passage=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.}}

A notable event which marks the beginning of such a period.

(astronomy) A precise instant of time that is used as a reference point.

(computing, uncountable) A precise instant of time that is used as a reference point (e.g. January 1, 1970, 00:00:00 UTC).