1 B2 idiomatic informal
To fall asleep or collapse from exhaustion.
"By nine o'clock she'd flaked out on the sofa — it had been a brutal week."
flake out
B2 informal intransitive
To fall asleep or become suddenly exhausted; or (especially American) to cancel plans unreliably.
In plain English
To suddenly fall asleep because you're very tired, or to let someone down by not showing up.
What does "flake out" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic informal
(Chiefly American) To fail to honour a commitment or social arrangement without a good reason.
"He was supposed to help me move, but he flaked out at the last minute."
Literal vs figurative
Words literally mean
Like a snowflake — something insubstantial that gives way and falls. The 'unreliable' sense extends this to a person who is flimsy or insubstantial.
Actually means
To suddenly fall asleep because you're very tired, or to let someone down by not showing up.
Usage tip
The 'fall asleep from exhaustion' sense is common in British and American English. The 'cancel plans/be unreliable' sense ('he flaked out on me') is more common in American English and often describes someone who is chronically unreliable. The person is often called a 'flake'.
Words that pair with "flake out"
Natural word combinations native speakers use most often.
exhaustion sofa chair plans commitment
How to conjugate "flake out"
The five tense forms you'll use most often.
Base
flake out
I/you/we/they
3rd person
flakes out
he/she/it
Past simple
flaked out
yesterday
Past participle
flaked out
have + pp
-ing form
flaking out
continuous
Hear "flake out" in the wild
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Other ways to say "flake out"
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