bacillus
C1-C2 / Academic / TechnicalFormal, Scientific, Medical
Definition
Meaning
A rod-shaped bacterium, often referring to those forming spores and sometimes causing disease.
In a broader, often figurative sense, any harmful influence or germ of corruption.
Linguistics
Semantic Notes
The term is specific in microbiology but can be used metaphorically. In non-scientific contexts, it often carries a negative connotation.
Dialectal Variation
British vs American Usage
Differences
Usage is identical in both varieties; the word is a technical term from Latin.
Connotations
Neutral in scientific contexts, potentially negative or ominous in metaphorical use (e.g., 'the bacillus of fanaticism').
Frequency
Low frequency in general discourse, common in medical, biological, and public health texts.
Vocabulary
Collocations
Grammar
Valency Patterns
The [DISEASE] bacillusa bacillus that [VERB]bacillus of [ABSTRACT NOUN (metaphorical)]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “The bacillus of doubt (metaphorical)”
- “To eradicate the bacillus of corruption (metaphorical)”
Usage
Context Usage
Business
Rare, except in biotech or pharmaceutical contexts.
Academic
Common in biology, medicine, microbiology, and public health papers.
Everyday
Very rare; might appear in news about disease outbreaks.
Technical
Standard term in microbiology for a specific morphological group of bacteria.
Examples
By Part of Speech
noun
British English
- The laboratory confirmed the presence of the anthrax bacillus.
- He spoke of combating the bacillus of racism in society.
American English
- Researchers isolated a novel soil bacillus.
- The article described fear as a social bacillus.
Examples
By CEFR Level
- Some bacilli can cause serious illness.
- Doctors study different bacilli.
- The tubercle bacillus is responsible for tuberculosis.
- Public health measures aim to control the spread of pathogenic bacilli.
- Bacillus anthracis spores can remain viable in soil for decades.
- The critic argued that the novel exposed the moral bacillus at the heart of the regime.
Learning
Memory Aids
Mnemonic
Think of 'bacillus' as a 'little staff' (from Latin 'bacillum', diminutive of 'baculum' meaning rod or staff), which describes its shape.
Conceptual Metaphor
A SMALL ROD/SHAPE IS A GERM; A GERM IS A SOURCE OF CORRUPTION.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with Russian 'бацилла' (bacilla), which is a direct cognate with identical meaning. Be aware of false friends like 'палочка' which is a more general term for 'rod' or 'stick'.
Common Mistakes
- Using 'bacillus' as a general synonym for 'virus' (they are biologically distinct).
- Incorrect plural: 'bacilluses' (correct: 'bacilli').
- Mispronunciation: /ˈbæs.ɪl.əs/ (stress is on the second syllable).
Practice
Quiz
In a metaphorical sense, 'bacillus' most likely refers to:
FAQ
Frequently Asked Questions
No. 'Bacillus' refers specifically to rod-shaped bacteria. 'Bacteria' is the broader domain including all shapes (cocci, spirilla, etc.).
Yes. Lowercase 'bacillus' refers to the shape. Uppercase 'Bacillus' refers to the specific genus of bacteria within that morphological group.
The correct plural is 'bacilli' (/bəˈsɪl.aɪ/).
No, it is incorrect. Bacilli are a type of bacterium, which is a prokaryotic cell. Viruses are acellular and much smaller, with a completely different structure and lifecycle.