Conceivable

Con*ceiv"a*ble (?), a. [Cf. F. concevable.] Capable of being conceived, imagined, or understood. "Any conceivable weight." Bp. Wilkins.

It is not conceivable that it should be indeed that very person whose shape and voice it assumed.
Atterbury.

-- Con*ceiv"a*ble*ness, n. -- Con*ceiv"a*bly, adv.