GDP

total goods and services produced by a nation during one year excluding payments on foreign investments (Economics)

A region's gross domestic product, or GDP, is one of the ways for measuring the size of its economy. The GDP of a country is defined as the total market value of all final goods and services produced within a country in a given period of time (usually a calendar year). It is also considered the sum of value added at every stage of production (the intermediate stages) of all final goods and services produced within a country in a given period of time. Until the 1992 the term GNP or gross national product was used in the United States. The two terms GDP and GNP are almost identical - and yet entirely different; GDP (or GDI - Gross Domestic Income) being concerned with the region in which income is generated. That is, what is the market value of all the output produced in a nation, the United States, for example, in one year. GDP concerns itself with where the output is produced and not who produced it. Meanwhile, GNP (or GNI - Gross National Income) is a measure of the accrual of income or the value of the output, produced by the "nationals" of a region. GNP concerns itself with who "owns" the production. If we take the USA as an example again, GNP measures the value of output produced by American firms, regardless of where the firms are located. This compares to GDP which is concerned with where the production takes place and not if the company is an American firm or not. Supposing that a firm can be defined as American in an economic world where most large firms are actually global groups.
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Noun
1. measure of the United States economy adopted in 1991; the total market values of goods and services by produced by workers and capital within the United States borders during a given period (usually 1 year)
(synonym) gross domestic product
(hypernym) value

See gross domestic product (GDP)    

The value of an economy’s total output of goods and services, less intermediate consumption, plus net taxes on products and imports. GDP can be broken down by output, expenditure or income components. The main expenditure aggregates that make up GDP are household final consumption, government final consumption, gross fixed capital formation, changes in inventories, and imports and exports of goods and services (including intra-euro area trade).

the total market value of all final goods and services produced in a country in a given year; equals total consumer, investment and government spending, plus the value of exports minus the value of imports.