The Collaborative International Dictionary of English v.0.48:

Lyopomata \Ly`o*po"ma*ta\, n. pl. [NL., fr. Gr. ? to loose + ?,
   ?, a lid.] (Zool.)
   An order of brachiopods, in which the valves of shell are not
   articulated by a hinge. It includes the Lingula, Discina, and
   allied forms. [Written also Lyopoma.]
   [1913 Webster]