UNDERGROUND ECONOMY

Is defined as all those economic activities which are not declared and which are outside the control of the State administration and its official statistics. In other words, any economic activity outside the regulated economy. Another concept for which it is known is the total volume of black money circulating in a country or, what is the same, the total of monetary transactions that are not declared to the tax authorities.
Translation:
DK: Undergrundsøkonomi
GR:Παραοικονομία
IT: Economia sommersa
PT: Economia paralela
SP: Economía sumergida