A liquor distilled from a type of maguey, or agave, which also harbours a particular worm or gusano. One of these short fat worms is added to each bottle of the drink. Some say that the smoky flavour of the drink derives from the worm, others that the worm gets its smoky flavour from the plant. In Oaxaca you may find a gusano or two fried and served at a restaurant. There is some suggestion that the worm in the bottle started with a commercial campaign to rid a bottler of a poor crop of maguey which was infested with worms. The gimic caught on.