A barrel-shaped double-sided drum - the classical drum of South Indian music, which is used as an accompaniment for vocal, instrumental and dance performances.

The body of the instrument was originally made of clay but these days is made of one piece of wood. Hollow, the body has two apertures of different size: one very small, that will generate high pitched sounds and another, wider, for low pitched sounds. The walls of the instrument are 2 or 3 centimetres thick and give it stability in the low frequencies. The goat skin, coupled to the high pitch aperture, wears a thick black disc made of flour, ferric oxid powder and starch stuck to its centre to allow the emission of harmonics. The skin coupled to the bass aperture is coated in its middle with plain flour paste to give it a perfect tune. The two skins are stretched together with leather strips.

The mridangam (or mrdangam) is the main rhythm instrument of Carnatic music with ghatam.