Enter a clue or pattern or both:

The Clue

Geology topic (3 letter answer)

The Answer

ERA

Tags


Notes

The answer ERA is very common and appears about once every 16 puzzles.

Related Clues

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Distinctive time
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A fixed point in time
Horse and buggy, e.g.
It contains periods
Koufax's was 2.76
Proposed 27th Amendment
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Good fig. for Maddux or Martinez

Definition

ERA as a noun:

1. (era, epoch) = a period marked by distinctive character or reckoned from a fixed point or event
2. (era, geological era) = a major division of geological time; an era is usually divided into two or more periods
3. (earned run average, ERA) = (baseball) a measure of a pitcher's effectiveness; calculated as the average number of earned runs allowed by the pitcher for every nine innings pitched