convenience vs lavatory

convenience and lavatory both are nouns.

Word	Noun	Adjective	Verb	Adverb
convenience	Yes	No	No	No
lavatory	Yes	No	No	No

As nouns, lavatory is a hypernym of convenience; that is, lavatory is a word with a broader meaning than convenience:

Other hypernyms of convenience include facility, bathroom, can, john, lav, privy, toilet.

convenience (noun)	lavatory (noun)
a device or control that is very useful for a particular job	a room or building equipped with one or more toilets
a toilet that is available to the public	a bathroom sink that is permanently installed and connected to a water supply and drainpipe; where you can wash your hands and face
the quality of being useful and convenient	a toilet that is cleaned of waste by the flow of water through it
the state of being suitable or opportune