The Oxford Thesaurus An A-Z Dictionary of Synonyms - extraneousadj.

1) unessential, non-essential, inessential, peripheral, superfluous, unnecessary, unneeded, extra, added, additional, adventitious, supernumerary, incidental, needless: Filter out all the extraneous substances. 2) not pertinent, impertinent, inapplicable, inapt, unapt, unfitting, inappropriate, unrelated, irrelevant, inapposite, unconnected, remote, alien, foreign, exotic, strange, outlandish, external, extrinsic, external, out of place, off the mark or point or subject, beside the point or mark: Why must you constantly bring up extraneous matters?