IPA: /ˈɛɡkʌp/
KK: /ˈɛgˌkʌp/
A small cup designed to hold an egg, especially when eating it directly from the shell.
She placed the soft-boiled egg in the eggcup before serving it for breakfast.
Eggcup → The word is formed from "egg" (from Old Norse *egg*, meaning the oval or round object laid by female birds) and "cup" (from Old English *cuppe*, meaning a small vessel for drinking). An eggcup is a small vessel designed specifically to hold an egg.
Think of an 'egg' being placed in a 'cup' — that's what an eggcup is, a small cup for holding an egg.
No commonly confused words.