indistinguishable

英 [ɪndɪ'stɪŋgwɪʃəb(ə)l] 美['ɪndɪ'stɪŋgwɪʃəbl]

1. exactly alike; incapable of being perceived as different;: "rows of identical houses"; "cars identical except for their license plates"; "they wore indistinguishable hats"

2. not capable of being distinguished or differentiated;: "the two specimens are actually different from each other but the differences are almost indistinguishable"; "the twins were indistinguishable"; "a colorless person quite indistinguishable from the colorless mass of humanity"