Tyrannion the Younger

Tyrannion, son of Artemidorus, was a Greek sophist from Phoenicia around the 1st century BCE. He was a pupil of Tyrannion of Amisus. He is also known as Tyrannion the Younger and his teacher as Tyrannion the Elder. His original name was Diocles, and changed it to Tyrannion to honor his teacher.
He became a slave during the war between Antony and Caesar and was purchased by a freedman of Caesar who was named Dymas. Later, he was given as a gift to Terentia, the wife of Cicero, who at some point freed him.
He taught at Rome as an eminent grammarian and established a school.
He wrote many books which are now lost, including the:

On Homeric Prosody
On the Parts of Speech
On the Roman Dialect
The Disagreement of Modern Poets with Homer
Exegesis of Tyrannio's Division of the Parts of Speech
Textual Criticism of Homer
Orthography

Walter Haas believed that the younger Tyrannion was spoken only as Diocles and in the Die Fragmente des Grammatikers Dionysios Thrax, Die Fragmente der Grammatiker Tyrannion und Diokles, attributes the 'Tyrannion' fragments to the Elder, while the 'Diocles' fragments to the Younger.
It is difficult for the modern historians to distinguish references of Tyrannion the Elder from Tyrannion the Younger/Diocles. In addition, there is a possibility that there was also a different separate Diocles which is difficult to be distinguished from Tyrannion the Younger/Diocles.