The bourgeoisie is the ruling class of capitalist society which possesses property in the means of production and which exists by exploiting wage labour. The source of income of the bourgeoisie is surplus value, which is created by unpaid labour and is appropriated by the capitalists.
The term denotes someone belonging to the urban middle-class, though in Marxist revolutionary parlance it had the negative connotation of the capital-owning class which the revolutionary proletariat had to overthrow and replace in economic and political power. In contemporary Marxist parlance it is used for the capitalist class as a whole.