brainiac

[ brey-nee-ak ]
/ ˈbreɪ niˌæk /
Slang.

noun

a highly intelligent person.

Origin of brainiac

from Brainiac, a superintelligent, villainous alien in the Superman comics, probably brain + (man)iac
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for brainiac

British Dictionary definitions for brainiac

brainiac

/ (ˈbreɪnɪˌæk) /

noun

informal a highly intelligent person

Word Origin for brainiac

C20: from a super-intelligent character in an American comic strip
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012