IPA: /ˈdaʊnˌhɪlə/
KK: /ˈdaʊnˌhɪlər/
A person who skis down hills or slopes, especially in competitive skiing.
The downhiller raced down the mountain at incredible speed.
Downhiller → It is formed from "down" (from Old English "dūn", meaning downward or lower) and "-er" (meaning a person who). The word "downhiller" refers to a person who goes downhill, typically in the context of skiing or biking.
Think of someone going 'down' ('dūn') a slope — the '-er' just means a person. A downhiller is someone who travels downhill.
No commonly confused words.