A Bubotuber is A magical plant, the observable part looks similar to a large black slug. Its surface has protrusions that are shiny, when squeezed pus is released that smells similar to petrol.
At Hogwarts School of Witchcraft and Wizardry, Bubotubers are generally covered in Fourth Year Herbology where students learn about Bubotuber pus extraction. The pus of the Bubotuber is used in various potions such as Healing Potions and were common in Fake protection potions.
“Bubotuber” appears to be a compound of “bubo” and “tuber,” the prior meaning a swelling of the lymph nodes like a blister,the latter referring to the fleshy, thickened, underground stem of a plant, which usually contains stored starch, like a potato. The name seems to be in reference to the appearance of the plant.