footfaulting
/ˈfʊtˌfɔltɪŋ/
noun
- In tennis and similar sports, an illegal serve where the server's foot touches or crosses the baseline before hitting the ball.
- The umpire called a footfaulting on her serve, costing her the point.
- He practiced his serve to avoid footfaulting during the match.
- Footfaulting is a common mistake among beginner tennis players.