cardines

from The Collaborative International Dictionary of English v.0.48

Cardo \Car"do\ (k[aum]r"d[-o]), n.; pl. {Cardines}.) [L., a
   hinge.] (Zool.)
   (a) The basal joint of the maxilla in insects.
   (b) The hinge of a bivalve shell.
       [1913 Webster]