offside
1. [ adverb ] illegally in advance of the ball or puck
2. [ adjective ] (sports) illegally beyond a prescribed line or area or ahead of the ball or puck
Synonyms: offsides
Examples:

"the touchdown was nullified because the left tackle was offside"

Related terms: onside sport
Similar spelling:   offsides
  off-site
  offsaddle
  offset
  offstage