I. a ‧ me ‧ ba /əˈmiːbə/ BrE AmE noun [countable]
an American spelling of ↑ amoeba
II. a ‧ moe ‧ ba BrE AmE ( also ameba American English ) /əˈmiːbə/ noun [countable]
[ Date: 1800-1900 ; Language: Modern Latin ; Origin: Greek amoibe 'change' ]
a very small creature that has only one cell
—amoebic adjective