A pivot grab (ふりむきつかみ Furimuki tsukami, Turned-around grab) is a type of grab that any character can use. While dashing, a character can pivot in the other direction, but at that exact same moment of pivoting, the player can press the grab button. In Brawl, this results in a grab that has longer reach than most normal grabs. The pivot grab can help grab opponents that constantly roll behind opponents that are dashing, and is useful as well as if a character predicts an unsafe approach.
Pivot grabs generally have less ending lag than a character's dash or standing grab. For some characters with extended grabs, this lag is substantially shorter; Yoshi, Ivysaur, and Lucas have pivot grabs that are so much faster to end than their normal grabs that it is their preferred method of grabbing. However, other characters with extended grabs (Zero Suit Samus, Link, and Toon Link) do not have this advantage, with pivot grabs not much faster than their normal ones.
Characters with high running speed and low traction cover more ground while pivot grabbing, resulting in a minor range increase.
In Melee
Pivot grabs in Melee are done out of the turn animation after the initial dash, not the run. Their hitboxes and animation is no different from normal standing grabs, though, and there is only one frame during the dash dance turnaround where it can be done. Regardless, the Melee pivot grab is still very useful, often being used to extend hard chain grabs or space around quick moves like Fox's or Falco's shine for a grab.