unicellular
/ˌjuːnɪˈseljʊlə(r)/adjective
1- Biology (of protozoans, certain algae, spores, etc.) consisting of a single cell.【生物】（原生动物, 海藻, 孢子等）单细胞组成的。
1.1
- (of an evolutionary or developmental stage) characterized by the formation or presence of a single cell or cells（进化, 发展阶段）单细胞的。