/ Thesaurus / B Synonyms of brainiac Find synonyms for: Noun1. genius, mastermind, brain, brainiac, Einstein, intellectual, intellectusage: someone who has exceptional intellectual ability and originality; "Mozart was a child genius"; "he's smart but he's no Einstein"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: devout Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language