IPA: //ˈweɪstˌkoʊtɪd//
KK: /ˈweɪstˌkoʊtɪd/
Dressed in a waistcoat, which is a type of clothing worn over a shirt and under a jacket.
He looked very stylish in his waistcoated outfit at the formal event.
Waistcoated → It is formed from 'waist' (from Old English 'waist', meaning the part of the body between the ribs and hips) and 'coat' (from Old French 'cote', meaning a garment or outer covering) with the suffix '-ed' (indicating a state or condition). The word 'waistcoated' refers to being dressed in a coat that covers the waist area.
Think of the 'waist' as the part of the body covered by a 'coat' — that's why 'waistcoated' means wearing a coat that covers the waist.
No commonly confused words.