earned run average

American  

[urnd ruhn av-er-ij, av-rij] / ˈɜrnd ˈrʌn ˌæv ər ɪdʒ, ˌæv rɪdʒ /

noun

Baseball.

1. a measure of the effectiveness of a pitcher, calculated by dividing the number of earned runs scored against the pitcher by the number of innings pitched and multiplying the result by nine: ERA

   His earned run average is currently a worrisome 6.21, as he has pitched 42 innings and given up 29 earned runs.

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Etymology

Origin of earned run average

First recorded in 1945–50

Example Sentences

With the Giants last season he went 4-11 with a 3.85 earned run average with 137 strikeouts in 152 innings pitched.

From Barron's • Feb. 10, 2026

Kershaw is 3-0 with a 1.33 earned run average in four starts this month.

From Washington Times • Jun. 26, 2023

In two seasons at Oklahoma, he played on College World Series teams in 1975 and 1976 and posted a 12-4 career record with eight saves and a 2.62 earned run average.

From Seattle Times • Jun. 20, 2023

But on the mound, an uncharacteristically shaky Dodgers pitching staff — which ranks 22nd in earned run average so far this season — stumbled once again.

From Los Angeles Times • Jun. 7, 2023

I think I had an earned run average of about one and a half in 1916.

From The Forest Monster of Oz by Evans, Bob