Wikipedia
Machairodontinae is an extinct subfamily of carnivoran mammals of the family Felidae (true cats). They were found in Asia, Africa, North America, South America, and Europe from the Miocene to Pleistocene living from about 23 million until about 11,000 years ago.
The Machairodontinae contain many of the extinct predators commonly known as " saber-toothed cats", including the famed genus Smilodon, as well as other cats with only minor increases in the size and length of their maxillary canines. The name means "dagger-tooth", from Greek μάχαιρα (machaira), dagger. Sometimes, other carnivorous mammals with elongated teeth are also called saber-toothed cats, although they do not belong to the felids. Besides the machairodonts, saber-toothed predators also arose in Nimravidae, Barbourofelidae, Machaeroidinae, Hyaenodontida and even in two groups of metatherians ( Thylacosmilidae sparassodonts and deltatheroideans).