suction
suc.tion \'s*k-sh*n\ n [LL suction-, suctio, fr. L suctus, pp. of sugere to su]ck - more at SUCK 1: the act or process of sucking 2a: the act or process of exerting a force upon a solid, liquid, or gaseous body by reason of reduced air pressure over part of its surface 2b: force so exerted 3: a device (as a pipe or fitting) used in a machine that operates by sucti on