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off·side(ôf′sīd′, ŏf′-) also off·sides (-sīdz′)
adv. & adj.
1. Sports Illegally ahead of the ball or puck in the attacking zone.
2. Football Illegally beyond the line of scrimmage when the ball is snapped or ahead of the ball when the ball is kicked on a kickoff.
An offside motion or play.