the area between two breast implants.
Look at that chick's ugly tattoo in her silicone valley!
by roarkfish July 15, 2006
Cleavage canyon, the area on the chest between the tits.
"That's a boob job, just look at the silicone valley."
by Jtron 3000 October 03, 2003
a girl who had a major and obvious boob job.
OMG Angela is so fake! Look at her new silicone valley!
by sourban May 16, 2008