IPA: /ˈhæŋˌdɔɡ/
KK: /hæŋˌdɔg/
Feeling sad or guilty, often with a downcast expression.
He had a hangdog look after forgetting his friend's birthday.
A person who is sneaky, dishonest, or morally bad.
He was known as a hangdog, always trying to cheat others.
Hangdog is formed from "hang" (from Old English "hangian", meaning to suspend or be suspended) and "dog" (from Old English "docga", meaning a dog or a powerful breed of dog). The term originally referred to a dog that was hanged or suspended, and it evolved to describe a person who appears dejected or guilty, as if they were hanging their head in shame.
Think of a dog that looks sad and is 'suspended' in its demeanor — that's why 'hangdog' describes someone who appears guilty or dejected.
No commonly confused words.