A vermis is a worm. In the field of medicine, a vermis is
any structure or part in the body that resembles a worm
in shape. A good example would be the vermis of the
cerebellum, (known as the cerebellar vermis; see
picture to the right) which is a worm shaped structure
located between both halves of the cerebellum. The
cerebellum is an area in the back, bottom part of the
brain that plays an important role in movement and
coordination. The appendix can also be described as a
type of vermis because it also a worm-like structure.
This is why is it also known as the vermiform (meaning
worm-like) appendix. The appendix a structure that is
attached to the first part of the large intestine (known
as the cecum) and has no known function in the human
The cerebellar vermis.
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Some parasites are worm-like in structure and can also be considered a type of vermis.
A parasite is any organism that lives in or on another living being, gains an advantage by
doing so, but causes disadvantage to the being it is living on. A good example would be
tapeworms, which are ribbon-shaped worms that live inside the intestines of humans or
of animals that have a spine. More than one vermis is called vermes.

Vermis comes from the Latin word "vermis" meaning "worm."
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