lav·a·to·ry 
(lăvə-tôr′ē)
(lăvə-tôr′ē)n. pl. lav·a·to·ries
1. A room equipped with washing and often toilet facilities; a bathroom.
2. A washbowl or basin, especially one permanently installed with running water.
3. A flush toilet.
[Middle English, piscina, from Late Latin lavātōrium, from lavātor, launderer, from Latin lavāre, to wash; see leu(ə)- in the Appendix of Indo-European roots.]