Practice Swing

Do you count a stroke for a ball hit with a practice swing?

There are 2 possible answers to this question, depending on the circumstances.

The ball was not yet "in play" (= not yet teed off). In that case, rule 18-2a/19 (Ball Moved Accidentally Prior to Tee Shot) applies.

In plain English: if a player takes a swing before playing from the teeing ground, in the course of which she accidentally strikes and moves the teed ball with her club, she is considered not to have made a stroke. Therefore, she must replace the ball on the tee and put it into play from there. The player does NOT incur a penalty.

The ball was "in play" (= after the tee shot was hit). In that case, rule 18-2a/20 (Ball in Play Moved Accidentally) applies.

Again in plain English: if a player makes a swing and accidentally moves her ball in play with her club, she is deemed not to have made a stroke, because she didn't intend to move the ball ("stroke" = the forward movement of the club made with the intention of striking at and moving the ball). She receives NO penalty under rule 18-2a/20. However, she incurs a PENALTY stroke under Rule 18-2a for moving her ball in play, and the ball must be replaced.