This word, translated from the Greek, means a cut (tome*) through the skin (derma).
Used literally, it is the name given to a special knife, used by plastic surgeons to cut skin grafts. The word is also used figuratively, in neurology, to refer to a strip of the body surface that receives its nerve supply from a given segment of the The main nerve trunk running down the spinal canal and connecting the individual’s mind and consciousness to the rest .... Our bodies are segmented, much like an earthworm, except that the segments are not as obvious in higher animals. Learning which parts of the body surface are supplied by which segments of the The main nerve trunk running down the spinal canal and connecting the individual’s mind and consciousness to the rest ... is an important part of a neurologist’s or neurosurgeon’s education.
* When used with reference to a large book, the word tome implies that the volume is a slice, or a part “cut out” of a larger work, such as an encyclopaedia.