toilet vs lav

toilet and lav both are nouns.

Word	Noun	Adjective	Verb	Adverb
toilet	Yes	No	No	No
lav	Yes	No	No	No

As nouns, toilet and lav are synonyms defined as:

Other synonyms of toilet include bathroom, can, john, lavatory, privy.

toilet (noun)	lav (noun)
the act of dressing and preparing yourself	a room or building equipped with one or more toilets
a room or building equipped with one or more toilets
a plumbing fixture for defecation and urination
misfortune resulting in lost effort or money