DEFINITION of 'Investment'. An asset or item that is purchased with the hope that it will generate income or appreciate in the future.In an economic sense, an investment is the purchase of goods that are not consumed today but are used in the future to create wealth.EFINITION of 'Investment'. An asset or item that is purchased with the hope that it will generate income or appreciate in the future. In an economic sense, an investment is the purchase of goods that are not consumed today but are used in the future to create wealth.