Definify.com
Webster 1913 Edition
Trochite
Tro′chite
,Noun.
 [Gr. [GREEK] a wheel.] 
(Paleon.) 
A wheel-like joint of the stem of a fossil crinoid. 
Webster 1828 Edition
Trochite
TRO'CHITE
,Noun.
 1.
  In natural history, a kind of figured fossil stone, resembling parts of plants, called St. Cuthbert's beads.  These stones are usually of a brownish color; they break like spar, and are easily dissolved in vinegar.  Their figure is generally cylindrical, sometimes a little tapering.  Two, three or more of these joined, constitute an entrochus.2.
  Fossil remains of the shells called trochus.