Synonyms for Gown (same or very similar meaning)
WordNet sense 1 (lingerie consisting of a loose dress designed to be worn in bed by women):
nightdress, nightgown, nightie, night-robe
WordNet sense 2 (protective garment worn by surgeons during operations):
scrubs, surgical gown
WordNet sense 3 (outerwear consisting of a long flowing garment used for official or ceremonial occasions):
robe
From the ODE community, based on WordNet
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