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

pinna \pin"na\, n.; pl. pinnae, e. pinnas. l., a
   feather.
   1. bot.
      a a leaflet of a pinnate leaf. see illust. of bipinnate
          leaf, under bipinnate.
      b one of the primary divisions of a decompound leaf.
          1913 webster

   2. zool. one of the divisions of a pinnate part or organ.
      1913 webster

   3. l. pinna, akin to gr. ?. zool. any species of pinna,
      a genus of large bivalve mollusks found in all warm seas.
      the byssus consists of a large number of long, silky
      fibers, which have been used in manufacturing woven
      fabrics, as a curiosity.
      1913 webster

   4. anat. the auricle of the ear. see ear.
      1913 webster
see also:
pinnae pinnas bipinnate leaf bipinnate pinna ear 

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

byssus \bys"sus\, n.; pl. e. byssuses; l. byssi.l. byssus
   fine flax, fine linen or cotton, gr. by`ssos .
   1913 webster
   1. a cloth of exceedingly fine texture, used by the ancients.
      it is disputed whether it was of cotton, linen, or silk.
      written also byss and byssin.
      1913 webster

   2. zool. a tuft of long, tough filaments which are formed
      in a groove of the foot, and issue from between the valves
      of certain bivalve mollusks, as the pinna and mytilus,
      by which they attach themselves to rocks, etc.
      1913 webster

   3. bot. an obsolete name for certain fungi composed of
      slender threads.
      1913 webster

   4. asbestus.
      1913 webster
see also:
byssuses byssi byss byssin pinna mytilus 

[3] : WordNet (r) 2.0

pinna
     n 1: division of a usually pinnately divided leaf syn: pinnule
     2: the externally visible cartilaginous structure of the
        external ear syn: auricle, ear
     also: pinnae pl
see also:
pinnule auricle ear pinnae 

Pinna >> P Words
Pinna, definition of term: Pinna
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