Balbus is a Roman cognomen that originally meant someone with a speech impediment or stutter.
One man named Balbus was the husband of the sister of Julius Caesar. His entire name was Marcus Atius Balbus. M. Atius Balbus was a senator and the father of Atia, who was the mother of Octavian (Augustus).
Another Balbus, Lucius Cornelius Balbus, from Spain, was instrumental in creating the first triumvirate of Caesar, Pompey, and Crassus. Pompey had been instrumental in getting Balbus his Roman citizenship, as a reward for service rendering in the fight against Quintus Sertorius, but while Pompey was away, Balbus was charged with obtaining his citizenship illegally. Cicero defended Balbus successfully. After the triumvirate disintegrated, Balbus supported Caesar, acting as his private secretaty, and then, after Caesar's death in 44 B.C., Octavian (Augustus). In 40 B.C. Balbus was made the first provincial-born consul.
Source: Encyclopedia Britannica