telephone circuit vs connecter

telephone circuit and connecter both are nouns.

Word	Noun	Adjective	Verb	Adverb
telephone circuit	Yes	No	No	No
connecter	Yes	No	No	No

As nouns, connecter is a hypernym of telephone circuit; that is, connecter is a word with a broader meaning than telephone circuit:

Other hypernyms of telephone circuit include connection, connective, connector, connexion.

telephone circuit (noun)	connecter (noun)
a telephone connection	an instrumentality that connects