Definition of screw back in English:
screw back
noun
Spin imparted to the cue ball by a player in striking it with the cue below the centre, causing it to move backwards after hitting the object ball.
Origin
Mid 19th century; earliest use found in John Roberts (1823–1893). From screw + back, after to screw back.
Pronunciation
screw back
/ˈskruː bak/