a raving or violently insane person; lunatic.
any intemperate or overly zealous or enthusiastic person: a maniac when it comes to details.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use maniac in a sentence
He was hardly reassured when members of the university’s board of trustees, following a special executive meeting convened by the governor in March, described Wallace as “scared,” “crazy,” and acting “like a raving maniac.”How Robert F. Kennedy Shaped His Brother's Response to Civil Rights | Patricia Sullivan | August 11, 2021 | Time
It would almost be less disturbing if he was showing some kind of sign he was a homicidal maniac.
Of course, Kim Jong-Un takes an image hit as a Katy Perry-obsessed, margarita-drinking maniac with daddy issues.I Was Honeydicked Into Spending Christmas with ‘The Interview’ | Allison McNearney | December 26, 2014 | THE DAILY BEAST
For as much as Walter was a maniac, he was at the forefront of printing art.Tim Burton Talks ‘Big Eyes,’ His Taste For the Macabre, and the ‘Beetlejuice’ Sequel | Marlow Stern | December 17, 2014 | THE DAILY BEAST
Tom Sizemore is, it seems, no longer a maniac—but he's convinced he can still play one onscreen.Tom Sizemore’s Revenge: On Tom Cruise’s Scientology Recruitment, Drugs, and Craving a Comeback | Marlow Stern | September 26, 2014 | THE DAILY BEAST
“It fell out of the window, I think,” says the little maniac.American Dreams: A Best-Selling Pint-Sized Psychopath | Nathaniel Rich | June 29, 2014 | THE DAILY BEAST
There, in the crush, he unceremoniously lost her, and sped like a maniac to the entrance gates.The Joyous Adventures of Aristide Pujol | William J. Locke
On each side of the driver of the galloping steeds stood a man, shouting like a maniac of the boatswain type.The Garret and the Garden | R.M. Ballantyne
We do not blame the maniac who burns a house down and brains a policeman, nor the mad dog who bites a minor poet.God and my Neighbour | Robert Blatchford
I regard Lucrezia Borgia as a homicidal maniac, and Torquemada as a religious maniac.God and my Neighbour | Robert Blatchford
But Lasseroe was a maniac now and he wanted to take the life away from the jewelry designer.
British Dictionary definitions for maniac
a wild disorderly person
a person who has a great craving or enthusiasm for something: a football maniac
psychiatry obsolete a person afflicted with mania
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