Definition of marginal utility in US English:

marginal utility

noun

Economics
  • The benefit gained from consuming one additional unit of a good or service.

    ‘the value of corn for this farmer would be determined by its marginal utility’
    • ‘There is a diminishing marginal utility of savings to any wealth holder, meaning the more you have, the less you need more.’
    • ‘Only with the use of money is it possible to compare the marginal utility of goods in all alternative employments.’
    • ‘Students can better understand diminishing marginal utility when a student is allowed to eat all of the chocolate cookies they want and stops eating at some point even though the cookies are free.’
    • ‘Gold is the monetary metal par excellence because it has constant marginal utility.’
    • ‘Its marginal utility tops off after about 10 listens.’