on the sidelines

Idioms  

1. Observing rather than taking part, out of the action, as in Bolivia's neighbors remained on the sidelines, waiting to see which faction in the dispute would prevail. This idiom comes from sports. The sidelines are the two lines defining the sides of the court or playing field and the area immediately beyond them where, in such sports as football, the non-playing team members sit. [First half of 1900s]

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Example Sentences

In 2022, James Bullard, then the president of the St. Louis Fed, spoke at an off-the-record, invitation-only Citigroup forum for clients on the sidelines of meetings of the International Monetary Fund.

From The Wall Street Journal • Jun. 19, 2026

Private-equity dealmaking also slowed down as buyers chose to sit on the sidelines.

From The Wall Street Journal • Jun. 18, 2026

Factoring in Scott McTominay's stomach bug this week, could Clarke leave one of his leading men on the sidelines for the biggest game the nation has seen in almost three decades?

From BBC • Jun. 13, 2026

"There is no reason to worry as far as there is no project," he told reporters on the sidelines of a summit in Montenegro last week.

From Barron's • Jun. 12, 2026

Grandmaster Miguel Najdorf, seated on the sidelines, likened the next game, the sixth, to a Mozart symphony.

From "Endgame" by Frank Brady