An expression usually used by chavs and the like who want to sound honest and trustworthy. Should (almost) always be interpreted as "I'm lying through my teeth".
"m8 i dont no were ur weed is i swear on me nans grave i dint steal it m8"
"kev i swear on me nans grave i aint never cheated on u"
see also: chav, charver
by narglewarglewoo May 20, 2016
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