nomogram

nomogram /nom·o·gram/ (nom´o-gram) a graph with several scales arranged so that a straightedge laid on the graph intersects the scales at related values of the variables; the values of any two variables can be used to find the values of the others.

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nomogram

[nom′əgram, nō′mə-]

Etymology: Gk, nomos, law, gramma, a record

1 a graphic representation, by any of various systems, of a numeric relationship.

2 a graph on which a number of variables are plotted so that the value of a dependent variable can be read on the appropriate line when the values of the other variables are given.

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nomogram

a graph with several scales arranged so that a straightedge laid on the graph intersects the scales at related values of the variables; the values of any two variables can be used to find the values of the others.

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tonography 

Technique for measuring the facility of outflow of aqueous humour from the eye under the continuous pressure exerted by the weight of a tonometer over a given period of time. The instrument usually employed for tonography is an electronically recording Schiötz tonometer. In this technique, the pressure is continuously recorded over a four-minute period and the outflow is deduced by utilizing a specifically designed diagram, called a nomogram (which is a graphical representation of one, or more, mathematical relationships whereby the desired value may be found without calculation by placing a straight edge across the diagram). The results of tonography can indicate the presence of established glaucoma, although the technique is not very reliable for borderline cases.

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nomogram

An alignment chart in which there are ≥ 3 abscissas, each measuring a specific parameter and mathematically or empirically defined as having a relationship to the other two; the abscissas are placed parallel to each other on an open 2-D field; a straight line drawn when 2 parameters are known allows determination of the value of a 3^rd–unknown parameter