"Medicine's ground state is uncertainty. And wisdom -- for both patients and doctors -- is defined by how one copes with it." Source:

Failure to know anything relevant for an economic decision, such as future variables, details of a technology, or sales. In models, uncertainty usually appears as a random variable and associated prob [..]

Result of the evaluation aimed at characterizing the range within which the true value of a quantity is estimated to lie, generally with a given likelihood. (ISO) The uncertainty is the amount of poss [..]

The difficulty of predicting an outcome due to limited knowledge of all components

late 14c., from uncertain + -ty.

The standard deviation of a sufficiently large number of measurements of the same quantity by the same instrument or method. Hence, the noncorrectable part of the inaccuracy of an instrument; it repre [..]

All events, both positive and negative whose probabilities are neither 0% nor 100%. Uncertainty is a distinct characteristic of the project environment. [D02229]

Uncertainty may be defined as imperfect knowledge.  Uncertainty and risk are terms that are often related.  Some economists distinguish between risk and uncertainty in terms of uncertainty representin [..]

The possibility that any number of things could happen in the future. In other words, the future is not known. This should be compared with risk, which is assigning probabilities to alternative possib [..]

being unsettled or in doubt or dependent on chance; "the uncertainty of the outcome"; "the precariousness of his income" doubt: the state of being u [..]

Something that is not known or established. Often considered synonymous with risk but is actually broader in scope because uncertainty includes both risks (negative outcomes) and opportunities (positi [..]

Definition Unmeasurable risk.

noun. the state or condition wherein something isn't correctly or totally acknowledged. 2. absence of confidence or conciseness in one's ideas, judgments, or aims.

A measure, often quantitative, of the degree of doubt or lack of certainty associated with an estimate of the true value of a parameter.

Synonym: error. A measure of the inherent variability of repeated measurements of a quantity. A prediction of the probable variability of a result, based on the inherent uncertainties in the data, fou [..]

  It is impossible to know exactly where something is and where it is going. This is a fundamental law of nature has a major effect on quantum theory.

A lack of full knowledge about a situation in, for example, risk assessment. Uncertainty can be reduced by carrying out more research.

 Uncertainty is a prominent feature of the benefits and costs of climate change. Decision makers need to compare risk of premature or unnecessary actions with risk of failing to take actions that subs [..]

See Measurement Uncertainty

Synonym: error. A measure of the the inherent variability of repeated measurements of a quantity. A prediction of the probable variability of a result, based on the inherent uncertainties in the data, [..]

half the range of the reading or (if reading are the same) the instrumental precision

An expression of the degree to which a value (e.g., the future state of the climate system) is unknown. Uncertainty can result from lack of information or from disagreement about what is known or even [..]

(n) being unsettled or in doubt or dependent on chance(n) the state of being unsure of something

An expression of the degree to which future climate is unknown. Uncertainty about the future climate arises from the complexity of the climate system and the ability of models to represent it, as well [..]

A state of incomplete knowledge that can result from a lack of information or from disagreement about what is known or even knowable. It may have many types of sources, from imprecision in the data to ambiguously defined concepts or terminology, or uncertain projections of human behaviour. Uncertainty can therefore be represented by quantitative me [..]

The condition in which reasonable Knowledge regarding Risks, benefits, or the future is not available.

The condition in which reasonable knowledge regarding risks, benefits, or the future is not available.

the lack of precise knowledge of the input values which is due to measurement error or to lack of knowledge of the steps required, and the pathways from hazard to risk, when building the scenario being assessed.

Nothing is more certain than the prevalence of uncertainty about the consequences of any economic decision. It is therefore entirely appropriate that ...

This article deals with individual decision making under uncertainty (unknown probabilities). Risk (known probabilities) is not treated as a separate ...

the expression of the amount of doubt that remains after a result is obtained. Although uncertainty may be subjective and without foundation ("We are 80% certain that nuclear fusion will be a pow [..]

A deficiency in knowledge concerning parameter values and the appropriate extrapolation of the significance of adverse health effects, to a situation involving different species and exposure condition [..]

The possibility that any number of things could happen in the future. In other words, the future is not known. This should be compared with risk, which is assigning probabilities to alternative possib [..]

If outcomes will occur with a probability that cannot even be estimated, the decisionmaker faces uncertainty. Contrast risk. This meaning to uncertainty is attributed to Frank Knight, and is sometimes [..]

See accuracy and precision. A general term to describe the level of variability of a result. In national forest monitoring, the term “uncertainty” is predominantly used in the policy context; it requi [..]

An expression of the combined errors in a test measurement process.