American Dictionary of the English Language

DISPROPORTIONABLE, adjective Disproportional; not in proportion; unsuitable in form, size or quantity to something else; inadequate. [Note. The sense in which this word is used is generally anomalous. In its true sense, that may be made disproportional, it is rarely or never used. The regular word which ought to be used is disproportional, as used by Locke.]