A player's movement without the ball. Similiar to Anticipation, this is how well a palyer particularly attacking ones, can assess a situation and then move off the ball, making themselves available to receive a pass in a dangerous postion.
Think of Michael Owen, always moving in and around defenders crearting space. It is ideal to have a striker with this atribute in the 16+ range if you have a good passer/playmaker in midfield like Arteta, Fabregas, Alonso ect.
Off the ball (or OTB) is a term used in football in the UK, usually associated with a players movement when not in possession of the football. It can also be used for incidents that happen not involving the ball, like a fight or a late challenge.