Hannya (般若) is a popular Japanese nō theatre mask design, representing a jealous female demon. It possesses two sharp bull-like horns, glaring eyes, and a leering mouth split from ear to ear.
- The character Hannya in the popular manga and anime series Rurouni Kenshin wears and takes his name from this mask
- Yoshimitsu from the Tekken and Soul Calibur games wears a Hannya mask in battle for some of his costumes.
- Some people also get tattoos with this style and there are books showing art focused on hannya masks.