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

rachis \ra"chis\ r=a"ki^s, n.; pl. e. rachises
   r=a"ki^se^z, l. rachides ra^k"i^d=ez.
   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
see also:
rachises rachides rhachis rhachis 

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

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
see also:
rhachises rhachides rachis rechis 

Rhachis >> R Words
Rhachis, definition of term: Rhachis
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