細 菌(さいきん)

さいきん

noun

bacteria, germ

medical

See also: 最近(さいきん) (recently (homophone))

1. bacteria, germ, microbe

Microscopic single-celled organisms. Used in both scientific contexts and everyday language when talking about hygiene, illness, and food safety.

細菌(さいきん)が繁殖(はんしょく)する。

Bacteria multiply.

手(て)を洗(あら)わないと細菌(さいきん)がつく。

If you don't wash your hands, germs will get on them.

この食中毒(しょくちゅうどく)は細菌(さいきん)が原因(げんいん)だと判明(はんめい)した。

It was determined that bacteria were the cause of this food poisoning.

Usage

A technical term used in both scientific and everyday contexts. Unlike the homophone 最近(さいきん) (recently), this word is written with different kanji and belongs to a completely different semantic field.

Common collocations

細菌(さいきん)が繁殖(はんしょく)する: bacteria multiply
細菌(さいきん)に感染(かんせん)する: to be infected with bacteria
細菌(さいきん)検査(けんさ): bacterial testing
細菌(さいきん)を殺(ころ)す: to kill germs

Similar words

ウイルス (virus) refers to a different type of pathogen. 細菌(さいきん) are living organisms that can be treated with antibiotics, whereas ウイルス cannot.

Related Words

Compare: ウイルス (virus (different pathogen type))

Synonym: ばい菌(きん) (germs (colloquial))

Related: 病原体(びょうげんたい) (pathogen)

Compare: 菌類(きんるい) (fungi)

Related: 病原菌(びょうげんきん) (pathogenic bacteria)

Related: 真菌(しんきん) (fungus)

Compare: 雑菌(ざっきん) (bacteria)

general

Added 2026.2.27 13:10 · Revised 2026.9.2 13:01

13500/13791_saikin