The Curtia Gens was a very ancient Roman family, whose roots came from the Sabine race. According to the historian Titus Livius, the Curtia Gens was one of the hundred families already existing at founding of Rome. The name of this gens came from the Latin curtus, which means "short" or "without a part of the body". It was used first as a nickname of a particular member of the Gens, then later as a first name (a praenomen), becoming at last the name of the entire Gens (a nomen). Some other Ancient Roman gentes took their names from physical qualities, like the famous Gens Flavia from the Latin flavus, meaning "blonde".
The Curtia Gens included several families, that each took their own surname (a cognomen), like "Philon", a family that produced Gaius Curtius Philon, Consul of the Roman Republic in 445 BC. Another famous surname was "Rufus", the family of the famous historian Quintus Curtius Rufus.
Read more about Curtius (gens): Legends of The Lacus Curtius, Other Notable Family Members