a. rare. [f. SUBSTITUTE v. + -ABLE.] Capable of being substituted.
1805. W. Taylor, in Ann. Rev., III. 312. It will always bear a regular proportion to that of other substitutable food.
c. 1820. Bentham, Language, Wks. 1843, VIII. 314. Substitute the singular to the plural number when substitutable without impropriety!
