bacteria
Definitions
Microscopic single-celled organisms, some helpful and some causing disease (plural of bacterium).
细菌（显微镜下的单细胞生物，有的有益、有的致病；bacterium 的复数）。
Root Breakdown
Root-derivedFrom Greek bakterion ('little rod'), named for the stick shape early scientists saw under the microscope. The -a ending is the Latin plural, so bacteria literally means 'rods' — the plural of bacterium.
Root bacter still carries 3 more wordsUsage Guide
Grammar trap: bacteria is plural, so 'bacteria are' is the careful form ('the bacteria are resistant'). Many people say 'bacteria is' casually, but avoid it in academic writing. Singular: a bacterium.
Example Sentences
- 1.
Harmful bacteria can multiply quickly in warm food.
- 2.
Not all bacteria are dangerous — many help us digest food.
- 3.
The wound became infected with bacteria.
Easily Confused
bacteria vs virus — Both cause illness, but bacteria are living single cells that antibiotics can kill; a virus is a much smaller particle that antibiotics do nothing against. A cold is viral; strep throat is bacterial.