1 definition by Sara B Ellum

Underpants, Underwear, be it Boxers, Briefs, Thongs, high rise, low rise, cotton, rayon, or polyester.

Grundles is actually short for grundlemires, as panties is short for underpants.
If you cut somebody off in traffic and they start flipping you off or shouting obscenities, simply say "Hey, don't get your grundles in a bundle, pal."
by Sara B Ellum December 21, 2010
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