public toilet vs public lavatory

public toilet and public lavatory both are nouns.

Word	Noun	Adjective	Verb	Adverb
public toilet	Yes	No	No	No
public lavatory	Yes	No	No	No

As nouns, public toilet and public lavatory are synonyms defined as:

public toilet and public lavatory: a toilet that is available to the public

Other synonyms of public toilet include comfort station, convenience, public convenience, restroom, toilet facility, wash room.

public toilet (noun)	public lavatory (noun)
a toilet that is available to the public	a toilet that is available to the public