The Clue
Geologists' divisions (4 letter answer)
The Answer
ERAS
Tags
Notes
The answer ERAS is very common and appears about once every 35 puzzles.
Related Clues
Ages
Epochs
Paleozoic, etc.
Periods
Actian and Augustan
Augustan and Actian
Big times
Blocks of history
Bullpen stats
Bygone times
Chapters in history
Christian and Caesarean
Christian and others
Depression and Prohibition
Eventful stretches
Historians' subjects
Historic periods
Historic times
Historical periods
History chapters
Mayan and Mundane
Mesozoic and Cenozoic
Momentous times
Mundane and Mayan
Notable periods
Significant periods
Spanish and Vulgar
Stretches of time
Time periods
Time spans
Timeline divisions
Timeline segments
Notable time periods
Theme-dominated times
They're full of dates
You were, to Caesar
You were, to Ovid
Spanish form of "to be" after "tú"
They're often associated with world leaders
They're sometimes named after presidents
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