berserk

American  

[ber-surk, -zurk] / bərˈsɜrk, -ˈzɜrk /

adjective

1. violently or destructively frenzied; wild; crazed; deranged.

   He suddenly went berserk.

   Synonyms:

   lunatic, demented, rabid, maniacal, mad, violent

   Antonyms:

   calm, rational

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noun

1. (sometimes initial capital letter) Also berserker. an ancient Norse warrior who fought with frenzied rage in battle, possibly induced by eating hallucinogenic mushrooms.

berserk British  

/ bəˈzɜːk, -ˈsɜːk /

adjective

1. frenziedly violent or destructive (esp in the phrase go berserk )

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noun

1. Also called: berserker.  a member of a class of ancient Norse warriors who worked themselves into a frenzy before battle and fought with insane fury and courage

Usage

What does berserk mean? Berserk describes violent, destructive, or deranged behavior. Berserk frequently describes someone who is acting wild, crazy, or deranged. It is commonly used with forms of the verb go, as in go berserk or went berserk, meaning someone suddenly erupted into a frenzy of angry or violent behavior. In Norse and Germanic folklore, a berserk (or berserker) is a warrior who worships the Norse god Odin, fighting savagely and without control, possibly from eating hallucinogenic mushrooms. They were said to wear shirts made of bearskin (see “Where does berserk come from?” below) and were often the villains in Norse sagas. Today, this sense is used figuratively to define any person who is prone to acting out angrily, especially without cause. Example: I told him that his music wasn’t even that great, and he went berserk.

Other Word Forms

• berserkly adverb
• berserkness noun

Etymology

Origin of berserk

1865–70; < Old Norse berserkr, equivalent to ber- (either *ber-, base of bjǫrn bear ² or berr bare ¹ ) + serkr sark, shirt, armor

Explanation

Berserk is another way of saying deranged, destructively violent, or unrestrained — like a wailing toddler ravaging the playroom when he's hopped up on sugar and long overdue for a nap. Famous writer and runner George Sheehan said, “If you want to win anything – a race, your self, your life – you have to go a little berserk.” He must have been thinking of the fierce Norse warriors called berserkrs that inspired the adjective we know to mean "crazed." Those warriors were feared to be fighters of superhuman strength who wore bear skins and chewed madly at their iron shields. It's safe to say most of their opponents ran away crying.

Example Sentences

The visiting Celtic fans away in the distance went berserk.

From BBC • Mar. 1, 2026

But it is the duo of Shannon and Macfadyen, portraying upright Americana and the American berserk, who are profound and unforgettable.

From The Wall Street Journal • Nov. 6, 2025

His rhetoric against our neighbor to the north has been simply berserk.

From Slate • Apr. 30, 2025

Even though its influences are prominent — classic two-reel silent shorts, vintage berserk animation, even something like “Caddyshack” — the artful insanity on display is very much its own.

From Los Angeles Times • Mar. 15, 2024

I came home with Legs, who went berserk when I brought her home.

From "Aristotle and Dante Discover the Secrets of the Universe" by Benjamin Alire Saenz