indistinguishable

adjective

in·​dis·​tin·​guish·​able ˌin-di-ˈstiŋ-gwi-shə-bəl 

-ˈstiŋ-wi-

: not distinguishable: such as

a

: lacking identifying or individualizing qualities

seemingly indistinguishable alternatives

The copy is practically indistinguishable from the original.

b

: not clearly recognizable or understandable

indistinguishable differences

c

: indeterminate in shape or structure

indistinguishable forms in the mist

indistinguishability

ˌin-di-ˌstiŋ-gwi-shə-ˈbi-lə-tē 

-ˌstiŋ-wi-

noun

indistinguishableness

ˌin-di-ˈstiŋ-gwi-shə-bəl-nəs 

-ˈstiŋ-wi-

noun

indistinguishably

ˌin-di-ˈstiŋ-gwi-shə-blē 

-ˈstiŋ-wi-

adverb

Synonyms of indistinguishable

• invisible
• imperceptible
• subtle

Examples of indistinguishable in a Sentence

indistinguishable differences that can be measured only electronically

indistinguishable shapes in the fog

Recent Examples on the Web

Thus the Marlowe played by Mitchum in the 1978 remake of The Big Sleep seems like an entirely different person from the original played by Bogart in 1946, despite their almost indistinguishable stories. — Harmon Siegel, Artforum, 1 Oct. 2026

Even after much tribulation, the researchers were finally able to test if photons traveling through the instrument’s circuits were indistinguishable. — Ameya Paleja, Interesting Engineering, 28 Sep. 2026

Inside the brain, physical and social pain are nearly indistinguishable. — George Loewenstein, Vogue, 28 Sep. 2026

Efficient, functional and increasingly indistinguishable from everything else. — Jennifer Jones, Forbes.com, 28 Sep. 2026

Word History

First Known Use

1606, in the meaning defined above

Rhymes for indistinguishable

• distinguishable
• inextinguishable
• undistinguishable

Kids Definition

indistinguishable

adjective

in·​dis·​tin·​guish·​able ˌin-dis-ˈtiŋ-gwish-ə-bəl 

: impossible to distinguish clearly