Pro*por"tion*al (?), a. [L. proportionalis: cf. F. proportionnel.]
1.
Having a due proportion, or comparative relation; being in suitable proportion or degree; as, the parts of an edifice are proportional.
Milton.
2.
Relating to, or securing, proportion.
Hutton.
3. Math. Constituting a proportion; having the same, or a constant, ratio; as, proportional quantities; momentum is proportional to quantity of matter.
Proportional logarithms, logistic logarithms. See under Logistic. -- Proportional scale, a scale on which are marked parts proportional to the logarithms of the natural numbers; a logarithmic scale. -- Proportional scales, compasses, dividers, etc. Draughting, instruments used in making copies of drawings, or drawings of objects, on an enlarged or reduced scale.
© Webster 1913.
Pro*por"tion*al, n.
1. Math.
Any number or quantity in a proportion; as, a mean proportional.
2. Chem.
The combining weight or equivalent of an element.
[Obs.]
© Webster 1913.