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

Poor countries that don’t have reserves to draw on and are on the sidelines of the AI boom are already struggling, with shortages closing factories and high import prices for energy straining threadbare government budgets.

From The Wall Street Journal • May 4, 2026

Trade Representative Jamieson Greer on the sidelines of a G7 meeting.

From The Wall Street Journal • May 4, 2026

This term, he has spent a long period on the sidelines injured.

From BBC • Apr. 30, 2026

Bernstein’s Stacy Rasgon stayed on the sidelines as well.

From MarketWatch • Apr. 24, 2026

Before the race, me and everybody else stood on the sidelines, clapping and hyping Ghost and Lu up as they took their marks.

From "Patina" by Jason Reynolds