#footfault  a fault that occurs when the server in tennis fails to keep both feet behind the baseline
  supertype:  fault.serve  (tennis or badminton or squash) a serve that is illegal (e.g., that lands outside the prescribed area); "he served too many double faults"
  part of:  lawn_tennis__tennis  a game played with rackets by two or four players who hit a ball back and forth over a net that divides the court

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