Pure cotton waistcoat. Waist belt fastening
The waistcoat (French term) is a type of jumper, completely closed, sleeveless, with various types of necklines (V- or U-shaped, to define two broad categories). It is a typically male garment.
In summer, for example, it is seen as a substitute for a jacket, over a short-sleeved shirt with a tie, combined with Bermuda shorts.
The waistcoat that is traditionally worn in formal or ceremonial situations, over the shirt and under the jacket, is more properly called a waistcoat, which is a completely different garment as it has buttons as fastenings; more sporty waistcoats, often made of heavy materials, are used in other areas such as sailing or cycling.
Women's waistcoats, especially since the late 1960s, have been used as the upper part of trouser suits, and unlike men's waistcoats they can be considerably longer, sometimes reaching down to the knee.