(adj) illegally beyond a prescribed line or area or ahead of the ball or puck, Syn. offsides, Ant. onside, Example:the touchdown was nullified because the left tackle was offside
adj. (Sports) Illegally beyond a prescribed line or area or ahead of the ball or puck; -- in sports such as football or hockey; as, the touchdown was nullified because the left tackle was offside. [ WordNet 1.5 ]