I found myself asking this question after seeing the site tmz.com show up all the time with breaking celebrity news… The answer is actually pretty interesting…

“‘TMZ’ stands for “Thirty Mile Zone,” a term which originated in the 1960’s. Due to the growth of ‘on location’ shoots, studios established a “thirty mile zone” to monitor the regulations of shooting throughout Hollywood. The zone was originally centered in Los Angeles around the old offices of The Association of Motion Pictures and Television Producers at Beverly and La Cienega Boulevards in California. It was often said that “Everything entertainment happens in the ‘Thirty Mile Zone.’” So essentially, the “Thirty Mile Zone” represents the epicenter of Hollywood! Interesting, huh?!”

Ya learn something new every day.