A dropbear or drop bear is a Australian marsupial. Drop bears are commonly said to be unusually large, vicious, carnivorous marsupials related to koalas (although the koala is not a bear) that inhabit treetops and attack their prey by dropping onto their heads from above.
Various methods suggested to deter drop bear attacks include placing forks in the hair, having Vegemite or toothpaste spread behind the ears or in the armpits, urinating on oneself, and only speaking English in an Australian accent.