Acronym pronounced pee-eye-vee. It stands for Penis in Vagina but when used in the form of an acronym, it is much like saying cool or awesome. Use it sparingly and only when the situation is the best of the best possible situations.
It was coined in 2003 by human sexuality guru, Kidder Kaper of the "Sex is Fun!" radio show.
Hot tubbing with naked chicks is PiV.
I won a PiV Porche in the lotto.
That threesome was PiV.