The verb to strap has two meanings: a) to bind, fasten or secure with a strap, b) to beat with a strap. Both meanings are used in spanking art and literature, but usually b) is what is meant.
A strap is a strip of pliant material such as leather. When used as an implement, it can be doubled up (if the strap is belt length), or the strap can have a handle by which it is held.
A strapping is a spanking or beating administered with a strap or belt. It is also sometimes called a leathering, a lashing or a stropping.
Strappings are given mostly either on the delinquent's hand or on their buttocks (spanking). For the hand, which is typically found in school corporal punishment, usually a shorter fairly stiff length of strap is used. For the buttocks, which is found in both school and domestic situations, either a similar kind of strap, or a longer, doubled-up strap is used. Straps with handles were mostly produced for school usage, especially in Britain, Ireland and in the Commonwealth.
Strapppings were also used in military and judicial corporal punishment. There, the strap was also sometimes applied to the delinquent's back instead of their buttocks.