To slide down hill; to slide on a sled, upon snow or ice.

As a form of locomotion, meaning to glide, slide, skid, or skate along without propulsive power, to coast [from the Latin for "rib," which came to mean "a slope down which one slides"] is divine. As a metaphor, meaning to proceed easily without special application of effort or concern, coasting is a dangerous sport; sometimes an idler must pedal, too. See: DISTRACTED.

a slope down which sleds may coast; "when it snowed they made a coast on the golf course"

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"

To move on a bicycle without pedaling.