Longman Dictionary of Contemporary English
Wiktionary
alt. A recreational slide with water flowing down it to reduce friction, sometimes involving the participant sitting on a mat or raft and sometimes leading into a pool at the bottom. n. A recreational slide with water flowing down it to reduce friction, sometimes involving the participant sitting on a mat or raft and sometimes leading into a pool at the bottom.
Wikipedia
A water slide (also referred to as flumes, water chutes, or hydroslides) is a type of slide designed for warm-weather or indoor recreational use at water parks. Water slides differ in their riding method and therefore size. Some slides require riders to sit directly on the slide, or on a raft or tube designed to be used with the slide.
A typical water slide uses a pump system to pump water to the top which is then allowed to freely flow down its surface. The water reduces friction so sliders travel down the slide very quickly. Water slides run into a swimming pool (often called a plunge pool) or a long run-out chute. A lifeguard is usually stationed at the top and the bottom of the slide, so that if a rider gets hurt they will be treated immediately.
Usage examples of "water slide".
Sprightly and bouncing, they climbed out of the pool and ran, much faster than the music, to the ladder of a water slide, climbed up--- down they came, Wheeee!
He watches the line of water slide slowly and evenly down the wall of the tub, and then with a crazed vortical cry the last of it is sucked down.
He had a moment to wonder how twilight had become dark midnight so suddenly, and to feel sad that the city's residents had doused all their lights, then he felt the water slide up and over him again.
He felt her soft hands caressing his face and felt cool water slide over his heated body.
An unhappy laugh and she went back to watching the water slide past.
He wanted nothing more than to be able to climb into the sink and feel the water slide all over his entire body.
Dazed, she watched a drop of water slide down his chest, over his stomach and disappear beneath the terry cloth.
I said, watching the clear water slide over the smooth brown pebbles.
They were carried along, as if on a water slide, and simply had to wait for the ride to be over.
He could see all the way to the amusement park, where the Ferris wheel and the roller coaster rose up, where the Sky Needle loomed over the Hang Out dance pavilion and the Super Water Slide stood next to the Beach Arcade.