onside

American  

[on-sahyd, awn-] / ˈɒnˈsaɪd, ˈɔn- /

adjective

Sports.

1. not offside; being within the prescribed line or area at the beginning of or during play or a play.

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onside British  

/ ˌɒnˈsaɪd /

adjective

1. sport (of a player) in a legal position, as when behind the ball or with a required number of opponents between oneself and the opposing team's goal line

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adjective

1. taking one's part or side; working towards the same goal (esp in the phrase get someone onside ) Compare offside

Etymology

Origin of onside

First recorded in 1840–50; on + side ¹

Example Sentences

The economists and politicians who make this case say that it would both help keep the public onside on decarbonisation and drive more rapid emissions reductions.

From BBC • Apr. 15, 2026

The striker's celebrations were cut short by the offside flag but a VAR review showed he was onside and the goal was given.

From Barron's • Feb. 21, 2026

On foreign policy, too, they have both sought to keep US President Donald Trump onside.

From Barron's • Feb. 11, 2026

Liam McArthur has been moving towards accepting that change and is now of the view that it is necessary to offer further reassurance to those he needs to keep onside.

From BBC • Feb. 4, 2026

Luma had to teach her team the basics of organized play—how to execute throw-ins, how to stay onside.

From "Outcasts United: An American Town, a Refugee Team, and One Woman's Quest to Make a Difference" by Warren St. John