%cercal%

a. [ Gr. ke`rkos tail. ] (Zool.) Of or pertaining to the tail. [ 1913 Webster ]

a. [ Gr. difyh`s double (di- = di`s- twice + fy`ein to produce) + ke`rkos tail. ] (Anat.) Having the tail fin divided into two equal parts by the notochord, or end of the vertebral column; protocercal. See Protocercal. [ 1913 Webster ]

a. [ Hetero- + Gr. &unr_; tail. ] (Anat.) Having the vertebral column evidently continued into the upper lobe of the tail, which is usually longer than the lower one, as in sharks. [ 1913 Webster ]

a. [ Homo- + Gr. &unr_; tail. ] (Zool.) Having the tail nearly or quite symmetrical, the vertebral column terminating near its base; -- opposed to heterocercal. [ 1913 Webster ]

/mhw> a. (Zool.) Having a long slender tail. [ PJC ]