caudal

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Of, at, or near the tail or hind parts; posterior.
• adjective Situated beneath or on the underside; inferior.
• adjective Similar to a tail in form or function.

from The Century Dictionary.

• Pertaining to or situated near the tail; having the nature or appearance of a tail. Specifically
• In anatomy, having a position or relation toward the tail when compared with some other part: the opposite of cephalic (which see). Thus, the neck is a caudal part of the body with reference to the head. See caudad.
• In entomology, pertaining to or on the end of the abdomen: as, a caudal style; a caudal spot.
• noun In ichthyology, the caudal fin of a fish.
• noun In anatomy a caudal or coccygeal vertebra. Abbreviated cd. in ichthyological formulas.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Of the nature of, or pertaining to, a tail; having a tail-like appendage.
• adjective (Zoöl.) the terminal fin (or “tail”) of a fish.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective anatomy Pertaining to the tail or posterior or hind part of a body.
• noun A caudal vertebra

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adverb toward the posterior end of the body
• adjective resembling a tail
• adjective situated in or directed toward the part of the body from which the tail arises
• adjective constituting or relating to a tail