noun
bacteria
bak-TEER-ree-uh
noun
1
Microscopic single-celled organisms, some helpful and some capable of causing disease.
"Washing your hands helps remove harmful bacteria before you eat."
"Not all bacteria are dangerous — some in your gut actually help you digest food."
How to Use Bacteria
Learner’s notesIn plain EnglishTiny single-celled living things found almost everywhere, some of which cause illness and others of which are harmless or even beneficial.
Common mistake
"Bacteria" is technically plural — the singular form is "bacterium," though many people casually use "bacteria" for both.
Easily confused with
Common pairings
harmful bacteria
kill bacteria
gut bacteria
Word Forms
bacteriae plural
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Washing your hands helps remove harmful _____ before you eat.
Etymology
From New Latin bactēria, taken from the Ancient Greek word for a small rod or staff, reflecting the rod-like shape of many bacteria.