Synonyms for Washbowl (same or very similar meaning)
WordNet sense 1 (a bathroom sink that is permanently installed and connected to a water supply and drainpipe; where you can wash your hands and face):
basin, lavatory, washbasin, washstand
WordNet sense 2 (a basin for washing the hands (`wash-hand basin' is a British expression)):
lavabo, handbasin, wash-hand basin
From the ODE community, based on WordNet
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