Saturniidae, members of which are commonly named the saturniids, is a family of Lepidoptera with an estimated 2,300 described species. The family contains some of the largest species of moths in the world. Notable members include the emperor moths, royal moths, and giant silk moths (or wild silk moths).
Adults are characterized by large, lobed wings, heavy bodies covered in hair-like scales, and reduced mouthparts. They lack a frenulum, but the hindwings overlap the forewings to produce the effect of an unbroken wing surface. Saturniids are sometimes brightly colored and often have translucent eyespots or "windows" on their wings. Sexual dimorphism varies by species, but males can generally be distinguished by their larger, broader antennae.