IPA: //ˈweɪskəʊt//
KK: /ˈweɪskəʊt/
A type of clothing that is worn over a shirt and usually under a jacket, often without sleeves and with buttons in the front.
He wore a stylish waistcoat to the wedding.
Waistcoat originates from the combination of '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). The word 'waistcoat' refers to a garment worn on the upper body that covers the waist area.
Think of the 'waist' as the part of the body it covers and 'coat' as a type of garment — a waistcoat is a garment that covers the waist.