[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 

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