General English

  • noun the fact of having two meanings.


  • noun something heard or seen which can be understood in more than one way, thus resulting in possible confusion


  • noun something which is not clearly defined


  • An uncertainty in the meaning of provisions of a contract, document or specification. Mere disagreement about the meaning of a provision does not indicate an ambiguity. There must be genuine uncertainty of meaning based on logical interpretation ofthe language used in the contract. Generally, ambiguities in contracts are construed against the drafter of the agreement.


  • Uncertainty in a result, or how to interpret it.
  • In servo systems, the seeking of more than one null position.

Health Economics

  • (written as Ambiguity)

    A term used by decision and game theorists in the context of certain kinds of decisions under uncertainty that, from the perspective of subjective utility theory, display a kind of bias in the human psyche. This poses problems for users of expected utility theory.

    Suppose there are two urns, each containing 100 balls, which are either red or black. One urn has 50 red and 50 black balls. The proportion of red and black balls in the other urn is unknown. You can draw one ball from one of the urns, without looking, and if you draw a red ball you win a hundred dollars. Which urn would you choose Most people choose the 50-50 urn, even though, if we take the view that there are insufficient reasons for discriminating between the two urns, there is no higher probability of getting a red than by picking from the other urn. When offered 100 dollars for a black ball, they also choose the 50-50 urn. They seem to be averse to the 'ambiguity' represented by the other urn and strongly prefer what is apparently clear-cut. This is also known as the Ellsberg paradox (Ellsberg, 1961).

  • synonymUncertainty Aversion

Information & Library Science

  • noun confusion arising from double meanings to words or writing


  • noun the fact of something being unclear because it can be understood in different ways