ENGLISH
REFERENCE

bacillus

n. countable
C1 Advanced US //bəˈsɪɫəs// UK //bˈæsɪləs// bacil·lus

n. a type of bacteria that is shaped like a small rod. These tiny organisms are found almost everywhere in nature, including in soil and water.

n. a rod-shaped bacterium, typically belonging to the genus Bacillus. These prokaryotes are often motile and can form endospores, allowing them to survive in harsh environments.


SIMPLE

The scientist identified a bacillus in the soil sample.

CONTEXTUAL

Certain species of bacillus are used in the production of antibiotics and other industrial enzymes.

COMPLEX

While many bacillus strains are harmless or even beneficial to the ecosystem, some can cause serious infections in humans if they enter the bloodstream through a wound.

Origin

Learned borrowing from Latin bacillus (“little staff, wand”), diminutive of baculum (“stick, staff, walking stick”).

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