A Malappuram katthi is a kind of dagger, used in northern parts of Kerala in ancient times. The dagger is unique in its physical appearance and features as it has a very light-weight holder made of deer horn. The blade is thicker on the top and very sharp and lines at the bottom. The blade continues to the handle and covers the handle in a small single strip. The dagger is 18 - 25 inches (46-64 cm) long.
<gallery><!-- Image with unknown copyright status removed: Image:Malappuram Kathi.jpg| Special dagger used in northern parts of Kerala --></gallery>
Legend has it that wounds sustained by Malappuram katthi are difficult to heal and often infections develop in wounds which take longer to heal. Some say this is because of the metallic combination of the dagger and the unique craftsmanship involved and the know-how of which has been passed on from generations and is restricted to only a few blacksmith families in northern parts of Kerala.