undies
n. B2 Upper Intermediate UK //ˈʌndiz// undies
n. a casual word for underwear. You use it when talking about your clothes in a friendly or informal way.
n. a colloquial term for underwear.
I need to wash my undies before the trip.
He asked his wife to bring a fresh pair of undies for the long flight.
und(erwear) + -ies.