Costus

costus Saussurea lappa, a plant of the Himalayan region whose root is sometimes used as a spice. It has been identified as one of the spices used in classical Rome, where its name was costum. Dalby (1996) records its use (along with a wide range of other aromatics) in Byzantine drinks, which featured numerous flavoured wines.

Costus turns up as an ingredient in the greensauce for which a recipe is given by Alexander Neckham (12th century ad) and occasionally in later medieval recipes. Generally, however, its profile in European kitchens has been a low one.