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Medical Dictionary

tail

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noun \ˈtā(ə)l\

Medical Definition of tail

  1. 1:  the rear end or a process or prolongation of the rear end of the body of an animal

  2. 2:  one end of a molecule regarded as opposite to the head; especially :  the end of a lipid molecule that consists of a nonpolar hydrocarbon chain and is opposite to the polar group <most surface-active agents have a long hydrophobic tail attached to a polar head—R. E. Kirk & D. F. Othmer>

  3. 3:  any of various parts of bodily structures that are terminal: asa:  the distal tendon of a muscleb:  the slender left end of the human pancreasc:  the common convoluted tube that forms the lower part of the epididymis

  4. 4:  the motile part of a sperm that extends from the middle piece to the end and comprises the flagellum

  5. 5:  a thin protein tube which forms part of the coat of some bacteriophages and through which DNA is injected into a cell

  6. tailed \ˈtā(ə)ld\play adjective
    tail·less \ˈtā(ə)l-les\play adjective



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