Cytokinesis is the process by which the nucleus of a cell divides into two daughter cells. Meiosis is the process by which a diploid cell divides into four daughter cells.
Cytokinesis involves the constriction (or shrinking) of the nuclear envelope, causing it to break down into two parts. It involves a series of events that are triggered by special proteins called mitotic spindle proteins.
Meiosis involves the separation of chromosomes into homologous pairs, as well as the breaking down of genetic information into parts that can be passed on to future generations.