Definitions
from The Century Dictionary.
 noun A graphic table for computation.
 noun A written rule or law.
from Wiktionary, Creative Commons Attribution/ShareAlike License.
 noun mathematics A
diagram in which the relationship between three variables is represented by a straight line or curve for each variable; the value of the third variable corresponding to particular values of the first two is obtained by drawing a straight line through the points on the first two curves that represent particular values of the first two variables and noting the point at which the line intersects the third line or curve.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
 noun a graphic representation of numerical relations
Etymologies
from Wiktionary, Creative Commons Attribution/ShareAlike License
Examples

Using the model, they plotted a mathematical graph, called a nomogram, which shows the relationship between women's age, the numbers of eggs retrieved and the predicted live birth rate.

(The tool is a kind of nomogram  a decisionmaking tool that combines individual information with best thinking from scientific research to create a personalized recommendation.

Reading for rotational speed (n) = 90 r.p.m. The rotational speed read from the nomogram is to be set at the milling machine (see Fig. 8 in section 2, 19  speed selector lever).
4. Settingup and operation of horizontal or vertical milling machines

They can also be read from the nomogram of the milling machine.
4. Settingup and operation of horizontal or vertical milling machines

 Fixing the cutting values (speed of rotation, feeding speed) according to the indications given on the nomogram or in a table for the appropriate milling machine.

The nomogram in Fig. 7.9 gives a random relation between biogas production and mechanical/electric power obtainable for diesel gas and Otto gas engines.

As some simplifying assumptions had to be made, the nomogram is to be seen as a planning instrument rather than for the final calculations in designing the system.

When filling into cardboard cartons the nomogram in Figure 41 is useful for determining the size of carton that is required.

Before using the nomogram, it is necessary to know the bulk density of the product (volume occupied by a known weight; usually 100 g).

Coomarasamy said doctors and patients could now use the nomogram, combined with other measures, called antimullerian hormone (AMH) and antral follicle count (AFC) tests, when making decisions about how much ovarian stimulation is needed to get the optimum number of eggs.
qms commented on the word nomogram
Computers, they teach now at school,
Displaced the beloved slide rule,
But give not a damn
For the old nomogram
Which once was an elegant tool.
January 7, 2018