The rate at which one good may be substitutes for another as a consumer moves along their indifference curve i.e. the rate at which consumers are willing to give up units of one good in exchange for more units of another good. Put another way, the MRS of good X for good Y is the amount of good Y that a person is willing to give up to obtain one additional unit of good X.
In a production function or a utility function, the ratio at which one argument (input) substitutes for another along an isoquant or indifference curve.
generally referring to either the rate at which the consumer is willing to substitute one good for another (without loss or gain of satisfaction, see also "indifference curve"); or the rate at which factor inputs can be exchanged in a production process without a change in the production (output) level. (see also "isoquant")
The number of units of good Y that must be given up if the consumer, after receiving an extra unit of good X, is to maintain a constant level of satisfaction.
A measure of how much of one good a consumer will give up, to get one more unit of another good while remaining equally satisfied.
The rate at which a person will give up good (the good measured on the -axis) to get more of good (the good measured on the -axis) and at the same time remain indifferent (remain on the same indifference curve).
In economics, the marginal rate of substitution (“MRS†for short) is the least-favorable rate at which an agent is willing to exchange units of one good or service for units of another. The MRS measures the value that the consumer places on one extra unit of a good or service, where the opportunity cost is quantified by amount of another sacrificed.