backroll

A backroll is a backward somersault in water, typically used by scuba divers entering from a boat—sitting on the edge and rolling backward into the sea.

In skateboarding and snowboarding, it's a backward aerial rotation.

The term also appears in painting, where backrolling means going over a freshly sprayed or brushed surface with a roller to ensure even coverage: We sprayed the primer, then backrolled it for better adhesion.