Rhachis

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Rachis \Ra"chis\ (r[=a]"k[i^]s), n.; pl. E. {Rachises}
     (r[=a]"k[i^]s*[e^]z), L. {Rachides} (r[a^]k"[i^]*d[=e]z).
     [NL., fr. Gr. "ra`chis, -ios.] [Written also {rhachis}.]
     1. (Anat.) The spine; the vertebral column.
        [1913 Webster]
  


     2. (Bot. & Zool.) Same as {Rhachis}.
        [1913 Webster]

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Rhachis \Rha"chis\, n.; pl. E. {Rhachises}, L. {Rhachides}. [See
     {Rachis}.] [Written also {rechis}.]
     1. (Anat.) The spine.
        [1913 Webster]
  
     2. (Bot.)
        (a) The continued stem or midrib of a pinnately compound
            leaf, as in a rose leaf or a fern.
        (b) The principal axis in a raceme, spike, panicle, or
            corymb.
            [1913 Webster]
  
     3. (Zool.)
        (a) The shaft of a feather. The rhachis of the
            after-shaft, or plumule, is called the hyporhachis.
        (b) The central cord in the stem of a crinoid.
        (c) The median part of the radula of a mollusk.
        (d) A central cord of the ovary of nematodes.
            [1913 Webster]