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 ;