English > geological era: 1 sense > noun 1, time| Meaning | A major division of geological time; an era is usually divided into two or more periods. |
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| Synonym | era |
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| Instances | Cenozoic, Cenozoic era, Age of Mammals | approximately the last 63 million years |
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| Mesozoic, Mesozoic era, Age of Reptiles | From 230 million to 63 million years ago |
| Paleozoic, Paleozoic era | From 544 million to about 230 million years ago |
| Part of | eon, aeon | The longest division of geological time |
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| Parts | period, geological period | A unit of geological time during which a system of rocks formed |
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| Broader | geological time, geologic time | The time of the physical formation and development of the earth (especially prior to human history) |
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| Spanish | época, era geológica, era, período |
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| Catalan | època, era |
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