Haemacytometer

from The Collaborative International Dictionary of English v.0.48

Haemacytometer \H[ae]m`a*cy*tom"e*ter\
   (-s[-i]*t[o^]m"[-e]*t[~e]r), n. [H[ae]ma + Gr. ky`tos a
   hollow vessel + -meter.] (Physiol.)
   An apparatus for determining the number of corpuscles in a
   given quantity of blood.
   [1913 Webster]