In biology|lang=en terms the difference between cleavage and fission
is that
cleavage is (biology) the repeated division of a cell into daughter cells after mitosis while
fission is (biology) the process by which a bacterium splits to form two daughter cells.
As nouns the difference between cleavage and fission
is that
cleavage is the act of cleaving or the state of being cleft while
fission is the process whereby one item splits to become two.
As a verb fission is
to cause to undergo fission.