extraneous

/ɛkˈstreɪniəs/

/ɛkˈstreɪniəs/

Other forms: extraneously

Extraneous means coming from the outside, like the extraneous noise you hear when you're in a theater and a train passes by. Extraneous can also mean not relevant or essential, like all the extraneous information in your long-winded science report.

In Latin, extra means outside, as in extraordinary "outside the ordinary," or extraterrestrial 'coming from outside earth.' (Bonus points––ding! ding!––if you knew that terra is Latin for "earth.") The meaning of extraneous also extends to more abstract things that come from the outside: extraneous details are ones that don't matter.

Definitions of extraneous

1. adjective

   not belonging to that in which it is contained; introduced from an outside source
   “water free of extraneous matter”

   synonyms: foreign

   adulterant, adulterating

   making impure or corrupt by adding extraneous materials
2. adjective

   coming from the outside
   “extraneous light in the camera spoiled the photograph”

   “relying upon an extraneous income”

   synonyms: external, outside

   extrinsic

   not forming an essential part of a thing or arising or originating from the outside
3. adjective

   not pertinent to the matter under consideration
   “an issue extraneous to the debate”

   synonyms: immaterial, impertinent, orthogonal

   irrelevant

   having no bearing on or connection with the subject at issue
4. adjective

   not essential
   “the ballet struck me as extraneous and somewhat out of keeping with the rest of the play”

   synonyms:

   extrinsic

   not forming an essential part of a thing or arising or originating from the outside