IPA: /ˈæntɪˌtʃæpəl/
KK: /ˈæntɪˌtʃæpəl/
A space or area located at the entrance of a chapel, often serving as a waiting area or vestibule before entering the main chapel.
The wedding guests gathered in the antechapel before the ceremony began.
Antechapel → It is formed from "ante-" (meaning before) and "chapel" (from Old French *chapelle*, meaning a small church or place of worship). The word refers to a space that is located before or in front of a chapel.
Think of a space that is 'before' ('ante-') a place of worship ('chapel') — that's what antechapel means.
No commonly confused words.