An amastigote is a

protist A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exc ...

cell that does not have visible external flagella or cilia. The term is used mainly to describe an intracellular phase in the life-cycle of trypanosomes that replicates. It is also called the leishmanial stage, since in '' Leishmania'' it is the form the parasite takes in the vertebrate host, but occurs in all trypanosome genera.

References

Kinetoplastids {{Protist-stub