Pivoting is a technique that lets a pivot.gifcharacter use attacks out of a dash. The technique makes use of the time frame at which a character turns during a dash; any normal ground options are available as if the character were standing still – smash attacks, grabs and tilts can occur here without the lag that usually comes from using these attacks after a dash.

Wiki: http://www.ssbwiki.com/Pivoting
MySC: https://www.youtube.com/watch?v=6vaR4RM-qr0