What is a financial or numerical limit placed on imports or exports called?

A financial or numerical limit placed on imports or exports is referred to as a quota. This mechanism is used by governments to control the amount of certain goods that can be imported or exported during a specific time period.

Quotas serve various purposes, such as protecting local industries from overseas competition, ensuring the availability of certain products in domestic markets, and maintaining trade balance. By setting a limit, a quota can help regulate market supply and prevent market saturation, which is essential in maintaining pricing and demand stability.

In contrast, a tariff is a tax imposed on imported goods, which increases their price and makes local products more competitive but does not limit the quantity. An embargo refers to a ban on trade with specific countries or the exchange of certain products and is typically implemented for political reasons. A subsidy involves government financial assistance to domestic producers, lowering their costs and encouraging production, rather than limiting imports or exports. Thus, the characterization of quotas distinctly aligns with the definition provided in the question.