Question: Who was the Thracian gladiator who defeated military commander Gaius Claudius Glaberin the Third Servile War?

Context paragraphs:
Oenomaus (rebel slave): Oenomaus was a Gaulic gladiator, who escaped from the gladiatorial school of Lentulus Batiatus in Capua.  Together with the Thracian Spartacus and the fellow Gauls Crixus, Castus and Gannicus, he became one of the leaders of rebellious slaves during the Third Servile War (73–71 BC)

Third Servile War: The Third Servile War, also called by Plutarch the Gladiator War and The War of Spartacus, was the last in a series of slave rebellions against the Roman Republic, known collectively as the Servile Wars.  The Third was the only one directly to threaten the Roman heartland of Italia.  It was particularly alarming to Rome because its military seemed powerless to suppress it.

Gannicus: Gannicus was a Celtic slave, who together with the Thracian Spartacus, Crixus, Castus and Oenomaus, became one of the leaders of rebel slaves during the Third Servile War (73–71 BC).  In the winter of 71 BC, Gannicus, along with Castus, broke off from Spartacus, taking a large number of Celts and Germans with them, marking the second detachment of the rebellion.  Gannicus and Castus met their end in Lucania near Mount Soprano (Mount Camalatrum), where Marcus Licinius Crassus, Lucius Pomptinus and Quintus Marcius Rufus entrenched their forces in battle and defeated them.

Gaius Claudius Marcellus Maior: Gaius Claudius Marcellus (Maior) (before 91 BCE – c. 48 BCE) was a Consul of the Roman Republic in 49 BCE.  He is known to historians as C. Claudius Marcellus "Major" to distinguish him from his homonymous cousin (with whom he is readily confused), Gaius Claudius Marcellus Minor, one of the Consuls of the previous year.

Battle of Aquae Sextiae: The Battle of Aquae Sextiae (Aix-en-Provence) took place in 102 BC.  After a string of Roman defeats (see Battle of Arausio), the Romans under Gaius Marius finally defeated the Teutones and Ambrones.  The Teutones and the Ambrones were virtually wiped out, with the Romans claiming to have killed 90,000 and captured 20,000, including large numbers of women and children who were sold into slavery later.  Some of the surviving captives are reported to have been among the rebelling Gladiators in the Third Servile War.

Cimbri: The Cimbri were an ancient people, either Germanic or Celtic who, together with the Teutones and the Ambrones, fought the Roman Republic between 113 and 101 BC.  The Cimbri were initially successful, particularly at the Battle of Arausio, in which a large Roman army was routed, after which they raided large areas in Gaul and Hispania.  In 101 BC, during an attempted invasion of Italy, the Cimbri were decisively defeated by Gaius Marius, and their king, Boiorix, was killed.  Some of the surviving captives are reported to have been among the rebelling gladiators in the Third Servile War.

Crixus: Crixus was a Gallic gladiator and military leader in the Third Servile War between Roman Republic and Slave rebels.  Born in Gaul, he was enslaved by the Romans under unknown circumstances and trained as a gladiator in Capua.  His name means "one with curly hair" in Gaulish.

Gaius Claudius Glaber: Gaius Claudius Glaber was a military commander of the late Roman Republic, holding the offices of legate and military praetor in 73 BC.  He was defeated in the battle of Mount Vesuvius against the forces of Spartacus during the Third Servile War.

Spartacus: Spartacus (Greek: Σπάρτακος "Spártakos "; Latin: "Spartacus;" c. 111–71 BC) was a Thracian gladiator who, along with the Gauls Crixus, Gannicus, Castus, and Oenomaus, was one of the escaped slave leaders in the Third Servile War, a major slave uprising against the Roman Republic.  Little is known about Spartacus beyond the events of the war, and surviving historical accounts are sometimes contradictory and may not always be reliable.  However, all sources agree that he was a former gladiator and an accomplished military leader.

Publius Varinius: Publius Varinius was a Roman praetor in 73 BC, proconsul in 72 BC, and an unsuccessful military commander during the Third Servile War.

Supporting paragraphs: Gaius Claudius Glaber Spartacus
Answer: Spartacus