Proportionable

Pro*por"tion*a*ble (?), a. Capable of being proportioned, or made proportional; also, proportional; proportionate. -- Pro*por"tion*a*ble*ness, n.

But eloquence may exist without a proportionable degree of wisdom.
Burke.

Proportionable, which is no longer much favored, was of our [i. e., English writers'] own coining.
Fitzed. Hall.