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

The 4,000-strong, sold-out crowd at Stormont were left disappointed as Sooryavanshi was again on the sidelines for the second T20, and an Indian response was expected.

From BBC • Jun. 28, 2026

While he normally stays on the sidelines for a full year after a new listing to let the initial IPO volatility settle, Graham made an exception for SpaceX.

From MarketWatch • Jun. 23, 2026

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

Europe risks "total technological irrelevance" if it fails to develop sovereign capabilities, the head of Canadian AI startup Cohere warned Thursday on the sidelines of the Vivatech trade fair in Paris.

From Barron's • Jun. 18, 2026

She sat on the sidelines under her blue bow like someone who had been dropped out of a history book.

From "Homesick" by Jean Fritz