amoebic

Examples from literature

The amoebae, one celled animals, smaller than a small pin-head, have existed unchanged since life began. 
These conditions he has shared with all forms of life from the amoeba to the civilized nation. 
Up to the present it has been assumed that the environment of the amoeba is that to which it has become adapted and which is favorable to its existence. 
We have the one-celled amoeba, the microscopic animals, and the lowest forms of animal life. 
When such a bacterium comes in contact with an amoeba, it is taken into its body by becoming enclosed in processes which the amoeba sends out. 

amoeba | American Dictionary

amoeba
us/əˈmibə/pluralamoebas or amoebae
biology
a type of organism that has one cell