geological era

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a major division of geological time;
an era is usually divided into two or more periods
• Syn:
era
• Hypernyms:
geological time, geologic time
• Instance Hyponyms:
Cenozoic, Cenozoic era, Age of Mammals, Mesozoic, Mesozoic era,
Age of Reptiles, Paleozoic, Paleozoic era
• Part Holonyms:
eon, aeon
• Part Meronyms:
period, geological period