tumbleset

tum·ble·set

T0407650 (tŭm′bəl-sĕt′)n. Lower Southern US See somersault.
[Blend of tumble and somerset (alteration of somersaut, variant of somersault).]

tumbleset

(ˈtʌmbəlˌsɛt) n (Gymnastics) Southern US a somersault