IPA: /ˈdaʊnˌkæst/
KK: /ˈdaʊnˌkæst/
Feeling sad or unhappy; having a low spirit.
After hearing the bad news, she had a downcast expression on her face.
Downcast is formed from "down" (meaning from a higher to a lower position) and "cast" (from Old Norse "kasta", meaning to throw). The word describes a state of being thrown down or feeling low in spirit.
Think of being 'thrown down' ('cast') from a higher place ('down') — that's why downcast means feeling low or dejected.
No commonly confused words.