Ahemacytometeris a device used in manual microscopic methods to count cells. It consists of a thick glass microscope slide with a grid etched into it. This grid allows for the counting of cells in a defined volume of fluid, making it possible to calculate the concentration of cells in a sample. The other options are not valid terms:

Hyamestometer: Not a recognized term.

Ccntraomctcr: Typographical error, not a valid term.

Hcmacountcr: Typographical error, not a valid term.