1 C1 idiomatic slang
To insist very emphatically that something is true, especially when the listener is skeptical.
"'You actually met him at the café?' 'Yeah, swear down, he was just sitting there on his own.'"
inseparable
swear down
C1 slang inseparable intransitive
British urban slang meaning to insist very emphatically that something is true; to swear that one is telling the truth.
In plain English
To promise very strongly that something is absolutely true, especially when someone doesn't believe you.
What does "swear down" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 idiomatic slang
Used as a standalone exclamation to assert one's honesty or to express emphatic agreement that something is true.
"'Did he really say that?' — 'Swear down! I couldn't believe it either.'"
inseparable
Literal vs figurative
Words literally mean
To swear (something) down (emphatically, pressing it upon the listener).
Actually means
To promise very strongly that something is absolutely true, especially when someone doesn't believe you.
Usage tip
Primarily British urban slang, especially London. Common among younger speakers and in informal conversation. Used as an emphatic assertion of honesty when the speaker feels they are not being believed. Often used as a standalone exclamation: 'Swear down!'
Words that pair with "swear down"
Natural word combinations native speakers use most often.
truth story claim fact word it
How to conjugate "swear down"
The five tense forms you'll use most often.
Base
swear down
I/you/we/they
3rd person
swears down
he/she/it
Past simple
sweared down
yesterday
Past participle
sweared down
have + pp
-ing form
swearing down
continuous
Hear "swear down" in the wild
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