Cast is the term used to describe sideways travel. It is caused by the centre of mass moving sideways as the body leaves the bed. Cast can be corrected by improving the take phase of the skill.
It is common to see casting in a back landing half twist to feet, the roller and cat twist.
Casting may also be combined with travel and gain, so when performing a skill the body may end up landing towards one of the corners of the bed, thus resulting in travel and casting, or gain and cast.