Parameter

[puh-ram-i-ter] /pəˈræm ɪ tər/

noun
1.
Mathematics.

2.
Statistics. a variable entering into the mathematical form of any distribution such that the possible values of the variable correspond to different distributions.
3.
Computers. a variable that must be given a specific value during the execution of a program or of a procedure within a program.
4.
Usually, parameters. limits or boundaries; guidelines:
the basic parameters of our foreign policy.
5.
characteristic or factor; aspect; element:
a useful parameter for judging long-term success.
/pəˈræmɪtə/
noun
1.
one of a number of auxiliary variables in terms of which all the variables in an implicit functional relationship can be explicitly expressed See parametric equations
2.
a variable whose behaviour is not being considered and which may for present purposes be regarded as a constant, as y in the partial derivative ∂f(x,y)/∂x
3.
(statistics) a characteristic of the distribution of a population, such as its mean, as distinct from that of a sample Compare statistic
4.
(informal) any constant or limiting factor: a designer must work within the parameters of budget and practicality
n.

1650s in geometry, from Modern Latin parameter (1630s), from Greek para- “beside, subsidiary” (see para- (1)) + metron “measure” (see meter (n.2)).

A geometry term until 1920s when it yielded sense of “measurable factor which helps to define a particular system” (1927). Common modern meaning (influenced by perimeter) of “boundary, limit, characteristic factor” is from 1950s. Related: Parametric.

parameter pa·ram·e·ter (pə-rām’ĭ-tər)
n.

par’a·met’ric (pār’ə-mět’rĭk) or par’a·met’ri·cal adj.
par’a·met’ri·cal·ly adv.
parameter [(puh-ram-uh-tuhr)]

A quantity or number on which some other quantity or number depends. An informal example is, “Depending on the traffic, it takes me between twenty minutes and an hour to drive to work”; here, “traffic” is the parameter that determines the time it takes to get to work. In statistics, a parameter is an unknown characteristic of a population — for example, the number of women in a particular precinct who will vote Democratic.

Note: The term is often mistakenly used to refer to the limits of possible values a variable can have because of confusion with the word perimeter.

formal argument