The name is sometimes thought to be Celtic in origin, from a root related to Old Irish golb, "paunchy, fat." Suetonius offers four possible derivations, including the Gaulish galba meaning "fat."
- Publius Sulpicius Galba Maximus, consul and dictator of the 3rd century BC, who fought against Hannibal
- Servius Sulpicius Galba (consul 144 BC), soldier, politician and orator of the 2nd century BC who served as consul in 144 BC
- Servius Sulpicius Galba (consul 108 BC), soldier, politician and orator of the 2nd century BC who served as consul in 108 BC
- Servius Sulpicius Galba (praetor 54 BC), politician and military officer of the 1st century BC
- Servius Sulpicius Galba, orator during the reign of Augustus
- Gaius Sulpicius Galba, consul in AD 22, oldest son of Ser. Sulpicius Galba
- Galba, Servius Sulpicius Galba, Roman Emperor AD 68–69, younger son of Ser. Sulpicius Galba
- See Xavier Delamarre, entry on galba, Dictionnaire de la langue gauloise (Éditions Errance, 2003), p. 174, and D. Ellis Evans, Gaulish personal names: a study of some Continental Celtic formations (Oxford: Clarendon Press, 1967), pp. 293, 297, 349.
- Other derivations from galbanum, a gum used in ancient medicine and chemical preparations; the medical treatment galbeum; and galbae, a type of insect: Suetonius, Galba 3, Bill Thayer's edition at LacusCurtius.