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

univalve \u"nivalve\, n. uni- + valve: cf. f. univalve.
   zool.
   a shell consisting of one valve only; a mollusk whose shell
   is composed of a single piece, as the snails and conchs.
   1913 webster

   note: most univalves are spiral and are the shells of
         gastropods, but many belong to cephalopods and
         pteropods. a large number of univalves belonging to the
         gastropods are conical, cup-shaped, or shieldlike, as
         the limpets.
         1913 webster univalve

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

univalve \u"nivalve\, univalved \u"nivalved\, a. cf. f.
   univalve. bot.  zool.
   having one valve; as, a univalve shell or pericarp.
   1913 webster

[3] : WordNet (r) 2.0

univalve
     adj : used of mollusks, especially gastropods, as snails etc.
           ant: bivalve
     n : a class of mollusks typically having a one-piece coiled
         shell and flattened muscular foot with a head bearing
         stalked eyes syn: gastropod
see also:
bivalve gastropod 

Univalve >> U Words
Univalve, definition of term: Univalve
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