Economic Definition of average cost. Defined.
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Term average cost Definition: The opportunity cost incurred per unit in the production of a good. This can be calculated by dividing the total cost of production by the quantity of output produced. While average cost is a general term relating cost and the quantity of output, three more specific average cost terms that are worth a closer look are average total cost, average variable cost, and average fixed cost. As long as you're looking into cost, you might want to spend a little time with the most important member of the cost family of terms, marginal cost.