The definition of dorsal is something related to the back or the upper side of a plant or animal.(adjective)
The fin on a shark's back is an example of something that would be described as dorsal.
See dorsal in Webster's New World College Dictionary
Origin: ME < ML dorsalis < L dorsualis < dorsum, the back
See dorsal in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Late Latin dorsālis
Origin: , from Latin dorsuālis
Origin: , from dorsum, back.
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