The term ERA OR RBI can be solved by the four letter word STAT. This term is used in baseball to refer to a statistic that measures a pitcher's performance. ERA stands for Earned Run Average and is calculated by dividing the number of earned runs allowed by the number of innings pitched. RBI stands for Runs Batted In and is a statistic that measures the total number of runs a batter has driven in. Both ERA and RBI are important statistics used to measure a player's performance.