public toilet vs convenience

public toilet and convenience both are nouns.

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

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

public toilet (noun)	convenience (noun)
a toilet that is available to the public	a device or control that is very useful for a particular job
	a toilet that is available to the public
	the quality of being useful and convenient
	the state of being suitable or opportune