Tarquin vs Tarquinius Superbus

Tarquin and Tarquinius Superbus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tarquin	Yes	No	No	No
Tarquinius Superbus	Yes	No	No	No

As nouns, Tarquin and Tarquinius Superbus are synonyms defined as:

Tarquin and Tarquinius Superbus: according to legend, the seventh and last Etruscan king of Rome who was expelled for his cruelty (reigned from 534 to 510 BC)

Other synonyms of Tarquin include Lucius Tarquinius Superbus, Tarquin the Proud, Tarquinius.

Tarquin (noun)	Tarquinius Superbus (noun)
according to legend, the seventh and last Etruscan king of Rome who was expelled for his cruelty (reigned from 534 to 510 BC)	according to legend, the seventh and last Etruscan king of Rome who was expelled for his cruelty (reigned from 534 to 510 BC)