univalve

• POS: Adjective, Noun
• HYPHEN: u=ni=valve

CIDE DICTIONARY

univalve, n. [Uni- + valve: cf. F. univalve.].

 A shell consisting of one valve only; a mollusk whose shell is composed of a single piece, as the snails and conchs.  [1913 Webster]
" 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, a. [Cf. F. univalve.].

 Having one valve; as, a univalve shell or pericarp.  [1913 Webster]

OXFORD DICTIONARY

univalve, adj. & n. Zool.
--adj. having one valve.
--n. a univalve mollusc.