Wiktionary
water park
n. an amusement park that features waterplay areas, such as water slides and splash pads
Wikipedia
Water park
A water park or waterpark is an amusement park that features water play areas, such as swimming pools, water slides, splash pads, spraygrounds (water playgrounds), lazy rivers, or other recreational bathing, swimming, and barefooting environments. Water parks in more current states of development may also be equipped with some type of artificial surfing or bodyboarding environment such as a wave pool or FlowRider.