1. Incapable of being made out or discerned; imperceptible.
1590. Shaks., Mids. N., II. i. 100. The queint Mazes in the wanton greene, For lacke of tread are vndistinguishable.
1645. Milton, Tetrach., 19. The Form by which the thing is what it is, is oft so slender and undistinguishable.
1768. H. Walpole, Hist. Doubts, 92. One does not learn any language … with a good, nay, undistinguishable accent, between Christmas and Easter.
1816. Scott, Old Mort., xxxvi. The city and port … became undistinguishable in the distance.
1872. Black, Adv. Phaeton, xii. 171. Two almost undistinguishable figures pacing along.
2. Incapable of being distinguished or discriminated; of which the different elements cannot be distinguished or recognized; inseparably alike.
1679. Dryden, Troil. & Cress., Pref. ¶ 26. It has been prov’d already that confus’d passions make undistinguishable characters.
1693. Humours Town, 128. Drunken Rakes, and dirty Beau’s,… besides a number of undistinguishable Mob.
1794. Gisborne, Walks Forest, III. 9. Where sunk the parting orb, and with the sky In undistinguishable splendor join’d.
1802–12. Bentham, Ration. Judic. Evid. (1827), V. 662. Hope and fear … run into one another and are undistinguishable.
1860. Pusey, Min. Proph., 124. The locust [-swarm] … becomes in a few hours one undistinguishable, putrifying, heaving mass.
b. Const. from. (Common in recent use.)
1686. Plot, Staffordsh., 380. Altogether undistinguishable from the best French wines.
1833–4. J. Phillips, Geol., in Encycl. Metrop. (1845), VI. 674/2. The badger (probably undistinguishable from the common European species).
1870. J. H. Newman, Gram. Assent, I. v. 112. That apprehension … may become almost undistinguishable from an inferential acceptance of the great truth.
† 3. Indiscriminate. Obs. rare.
1702. Eng. Theophrast., 86. An undistinguishable Facility shall never fail of meeting with an undistinguishable Infidelity.
Hence Undistinguishableness.
1727. Bailey (vol. II.).
1843. Mill, Logic, I. iii. § 11. 93. Resemblance, when it exists in the highest degree of all, amounting to undistinguishableness, is often called identity.
1878. E. White, Life in Christ (ed. 3), III. xx. 289. The undistinguishableness of generic difference in character.
