Trunk has several meanings in the field of medicine. First, it
can refer to the main part of a nerve, vessel (a tube that a
body fluid passes through), or a collection of tissues before it
splits off or divides. The trunk, in this sense of the word, is
also known as a truncus.

Trunk can also refer to a large collecting lymphatic vessel. A
collecting lymphatic vessel is a tube that lymph passes
through. Lymph is a watery liquid produced by the body that
helps protect it against diseases.

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The human trunk
Most commonly, however, trunk refers to all of the parts of the body, except the neck,
head, arms, and legs. The neck, arms, and legs all extend from the trunk. Thus, it is the
center part of the body and consists of the chest and abdominal (belly) area. The lower
trunk is one area that can be affected in paraplegia. Paraplegia is a loss of the ability to
move and/or feel both legs and generally, the lower trunk (stomach area and lower back).

Most of the critical organs of the body are found within the trunk such as the heart, lungs,
kidneys, stomach, liver, intestines, the urinary bladder, and the anus (from which feces is
released). The trunk, in this sense of the word, is also known as the torso.

More than one trunk is referred to a trunci. Trunk comes from the Latin word "truncus"
meaning "trunk."
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