Lavatory is defined as a bathroom with a toilet and washbowl, or can also refer to just the toilet.
(noun)See lavatory in Webster's New World College Dictionary
noun pl. lavatories
Origin: LL lavatorium < L lavare, to wash: see lave
See lavatory in American Heritage Dictionary 4
noun pl. lav·a·to·ries
Origin:
Origin: Middle English, piscina
Origin: , from Late Latin lavātōrium
Origin: , from lavātor, launderer
Origin: , from Latin lavāre, to wash; see leu(ə)- in Indo-European roots
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