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

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

From BBC • Apr. 30, 2026

The agreement was also signed by her Croatian counterpart Andrej Plenkovic on the sidelines of a Three Seas Initiative summit in Dubrovnik.

From Barron's • Apr. 28, 2026

On top of that, market volatility pushed many to sell on days that the market rallied, and sit on the sidelines instead of buying dips.

From MarketWatch • Apr. 27, 2026

He also wants his firm to have capital on the sidelines in case of an economic slowdown.

From The Wall Street Journal • Apr. 19, 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