big-boy pants
big-boy pants · big-boy pantses
Pull-up underwear worn by a boy during and after toilet training, as contrasted to the…Pull-up underwear worn by a boy during and after toilet training, as contrasted to the diapers worn during infancy.
Meaning
2 senses(informal, plural, plural only)Pull-up underwear worn by a boy during and after toilet training, as contrasted to the diapers worn during infancy.
(figuratively, informal, plural, plural only)A notional pair of trousers or underwear worn by a male when acting maturely.
Origin
From big boy.From big boy.
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