This is the 6886th most frequent Chinese word.
滑
"滑" means "slippery" or "smooth."
In this case, '滑' is part of the compound noun '滑梯', where it conveys the meaning of 'sliding' as related to a slide.
这个滑梯很好玩。
This slide is very fun.
Here, '滑' is used as an adjective describing the state of being 'slippery'.
鱼的皮很滑。
The fish's skin is very slippery.
Here, '滑' is used as a verb meaning 'to slip'.