Paleozoic, e.g. (3)
I believe the answer is:
era
(Other definitions for era that I've seen before include "Age marked by a distinctive character" , "Important historical period" , "Memorable period" , "Series of years" , "Significant time" .)
I believe the answer is:
era
(Other definitions for era that I've seen before include "Age marked by a distinctive character" , "Important historical period" , "Memorable period" , "Series of years" , "Significant time" .)