indistinguishable

UK: /ˌɪndɪˈstɪŋgwɪʃəb^əl/ US: (in′di sting′gwi shə bəl)

WordReference Random House Unabridged Dictionary of American English © 2025

in•dis•tin•guish•a•ble  (in′di sting′gwi shə bəl), adj. 

1. not distinguishable.
2. indiscernible;
   imperceptible.

• in-³ + distinguishable 1600–10

in′dis•tin′guish•a•ble•ness, in′dis•tin′guish•a•bil′i•ty, n. 
in′dis•tin′guish•a•bly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

indistinguishable / ˌɪndɪˈstɪŋɡwɪʃəb^əl/ adjective

1. (often postpositive) followed by from: identical or very similar (to): twins indistinguishable from one another
2. not easily perceptible; indiscernible

ˌindisˌtinguishaˈbility, ˌindisˈtinguishableness noun

ˌindisˈtinguishably adverb