A more thorough explanation:

Definition: Octroi (ok-troy or ahk-trwah) is a French term that has several meanings:

1. Historically, it referred to a grant or privilege of a charter by a sovereign.
2. It can also refer to a local tax that is levied on certain goods that are brought into a city, especially in some European countries.
3. The place where such a tax is collected is also called an octroi.
4. The agency responsible for collecting such a tax is also referred to as an octroi.

For example, in some European cities, an octroi tax may be levied on goods such as alcohol, tobacco, and fuel that are brought into the city. The octroi is usually collected at a checkpoint or toll booth at the city's entrance.

Another example of octroi is the octroi de mer, a tax on imported goods that is collected in some French overseas territories.

These examples illustrate how octroi is a tax that is collected on certain goods that enter a city or territory. The tax is used to generate revenue for the local government and to regulate the flow of goods into the city or territory.