indistinguishable

1 not perceptible by a sense or by the mind indistinguishable differences that can be measured only electronically Synonyms impalpable, inappreciable, imperceptible, insensibleRelated Words inaudible, intangible, invisible; inconspicuous, indistinct, unnoticeable, unseeable, unseen; faint, insignificant, liminal, slender, slight, subtle, trivial; buried, concealed, covert, disguised, hidden, obscure, shrouded, unapparent, vagueNear Antonyms audible, observable, recognizable, tangible, visible; clear, conspicuous, evident, eye-catching, manifest, noticeable, obvious, plain, prominent, striking; apparent, distinct, significant, straightforwardAntonyms appreciable, discernible (also discernable), palpable, perceptible, ponderable, sensible

2 not seen or understood clearly indistinguishable shapes in the fog Synonyms blear, bleary, blurry, dim, foggy, fuzzy, gauzy, hazy, indefinite, indistinct, faint, misty, murky, nebulous, obscure, opaque, pale, shadowy, unclear, undefined, undetermined, vagueRelated Words dark, dusky, gloomy; impalpable, inappreciable, intangible, invisible; hieroglyphic (also hieroglyphical), incomprehensible, indecipherable, indiscernible, inexplicable, mysterious, obfuscatory, puzzlingNear Antonyms bright, distinct, evident, obvious, plain; certain, firm, strong, sureAntonyms clear, definite, pellucid

3 resembling another in every respect a synthetic fabric that supposedly is indistinguishable from real silk Synonyms coequal, duplicate, equal, even, identical, sameRelated Words akin, alike, analogous, comparable, coordinate, correspondent, corresponding, equivalent, like, look-alike, matching, parallel, similar, such, suchlike, synonymous, tantamountNear Antonyms differentiable, discriminable; divers, miscellaneous, sundry, varied, variousAntonyms different, disparate, dissimilar, distant, distinct, distinctive, distinguishable, diverse, nonidentical, other, unalike, unlike