Arrowroot powder, also known as "Neela Koovapodi" in Malayalam, is a starch extracted from the roots of the arrowroot plant, Maranta arundinacea. It's a fine, white powder widely used as a gluten-free thickening agent in cooking and baking, particularly in South India and Kerala. It's also known for its medicinal properties and is traditionally used for digestive issues and as a cooling agent.