Proportional

Part of speech: noun (n.)

1. Any number or quantity in a proportion; as, a mean proportional.

2. The combining weight or equivalent of an element. [Obs.]

Part of speech: adjective (a.)

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.