1 C1 idiomatic slang
To suddenly behave in a very strange, irrational, or erratic way.
"He totally wacked out when he heard the news and started shouting at everyone."
inseparable
wack out
C1 slang inseparable intransitive
To behave in a strange, erratic, or crazy way; to lose one's composure.
In plain English
To start acting really weird or crazy, or to lose control of yourself.
What does "wack out" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 idiomatic slang
(Of a device or system) to malfunction or stop working properly.
"My laptop just wacked out in the middle of my presentation — the screen went blank."
inseparable
Literal vs figurative
Words literally mean
To 'wack' something out — slang origin; 'wack' meaning crazy or bad.
Actually means
To start acting really weird or crazy, or to lose control of yourself.
Usage tip
Primarily American slang; uncommon in British English. The spelling 'whack out' also appears. Mostly used in casual speech among younger speakers. May also be used to describe a malfunctioning object.
Words that pair with "wack out"
Natural word combinations native speakers use most often.
completely totally suddenly person system
How to conjugate "wack out"
The five tense forms you'll use most often.
Base
wack out
I/you/we/they
3rd person
wacks out
he/she/it
Past simple
wacked out
yesterday
Past participle
wacked out
have + pp
-ing form
wacking out
continuous
Hear "wack out" in the wild
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Other ways to say "wack out"
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