IPA: /ˈhɪl.saɪd/
KK: /ˈhɪlˌsaɪd/
The area or slope of land on the side of a hill, located between the bottom and the top.
The children played on the hillside, enjoying the beautiful view.
Hillside → It is formed from "hill" (from Old English *hyll*, meaning a raised area of land) and "side" (from Old English *sīde*, meaning the lateral surface of something). The word "hillside" refers to the side or slope of a hill.
Picture a raised area of land ('hill') with a lateral surface ('side') — that's what a hillside is.
No commonly confused words.