Ad is short for advantage. The person (or side) with the Ad has a one point advantage over the other person. If that person wins the point, then the game goes to them. If they lose the point, then it goes to Deuce.
Advantage
the server
The ad side of a tennis court is the players left side. Or the opponents right side.
International Tennis Federation.
It is either ad in or ad out. If the server won the point it is ad in and if the returner won the point then it is ad out.
It stands for Women's Tennis Association
When serving or returning, there is a deuce side and an ad side. The deuce side is on the right, the ad side is on the left.
ATP stands for the Association of Tennis Professionals.
ad in, Ashe
The acronym AD stands for Anno Domini.
Ursula Mayes
Domini