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

theca \the"ca\, n.; pl. thecae. l., fr. gr. ? a case to put
   anything in. see tick a cover.
   1. a sheath; a case; as, the theca, or cell, of an anther;
      the theca, or spore case, of a fungus; the theca of the
      spinal cord.
      1913 webster

   2. zool.
      a the chitinous cup which protects the hydranths of
          certain hydroids.
      b the more or less cuplike calicle of a coral.
      c the wall forming a calicle of a coral.
          1913 webster
see also:
thecae tick 

[2] : WordNet (r) 2.0

theca
     n 1: a case or sheath especially a pollen sac or moss capsule
          syn: sac
     2: outer sheath of the pupa of certain insects
     also: thecae pl
see also:
sac thecae 

Theca >> T Words
Theca, definition of term: Theca
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