S: (n) slide, glide, coast (the act of moving smoothly along a surface while remaining in contact with it) "his slide didn't stop until the bottom of the hill"; "the children lined up for a coast down the snowy slope"
S: (n) motion, movement, move (the act of changing location from one place to another) "police controlled the motion of the crowd"; "the movement of people from the farms to the cities"; "his move put him directly in my path"