WAG is an acronym that stands for "wives and girlfriends," typically referring to the female partners of high-profile sportsmen and women. The term originated in British tabloid press, particularly gaining popularity during the 2006 FIFA World Cup to describe the partners of England national football team members. It is often used to refer to celebrity partners in sports and sometimes criticized as being demeaning to women.
The word "wag" also has other meanings such as a quick side-to-side movement (like a dog's tail wagging) or a witty person, but in the context of the acronym WAG, it specifically refers to wives and girlfriends of athletes or celebrities.