Dictionary definition · extraneous
adjective
- not pertinent to the matter under consideration"an issue extraneous to the debate"
- not essential"the ballet struck me as extraneous and somewhat out of keeping with the rest of the play"
- not belonging to that in which it is contained; introduced from an outside source"water free of extraneous matter"
- coming from the outside"extraneous light in the camera spoiled the photograph"
Source: Open English WordNet (CC BY 4.0).