Undeclarable

a. (UN-¹ 7 b and 5 b.)

c. 1449.  Pecock, Repr., II. xvi. 245. Of the spirit and of the ymage to gidere in an vndeclarable maner schulde be maad a sensible God.

1675.  Penn, Summons to Christendom, Wks. 1782, III. 319. Oh the peace, the joy, the pleasure and the undeclarable comfort!