ばい菌きん

ば

い

き

ん

Common wordJLPTN1Freq.FrequencyTop 50,000

Meanings

Everyday word for germs or bacteria, especially in contexts of hygiene, sickness, wounds, and dirtiness. Less scientific than 細菌.

傷きず口ぐちにばい菌きんが入はいると、腫はれることがある。
If germs get into a wound, it can swell up.
手てを洗あらってばい菌きんを落おとそう。
Let's wash our hands and get rid of the germs.

noun

filthy or harmful thing; vermin

Figurative and negative use for something, or sometimes someone, treated as dirty, harmful, or contemptible. Often appears in expressions such as ばい菌扱い and can sound insulting or bullying.

人ひとをばい菌きん扱あつかいするのはひどい。
It is cruel to treat someone like something filthy.
彼かれはクラスでばい菌きん呼よばわりされた。
He was called a germ by his classmates.

See all 13 example sentences ›

Usage patterns

〈物もの〉にばい菌きんがつくfor germs to get on something
手てにばい菌きんがついているから、よく洗あらいなさい。
There are germs on your hands, so wash them well.
〈人ひと〉をばい菌きん扱あつかいするto treat someone as if they were filthy or contemptible
クラスの子こにばい菌きん扱あつかいされて、悲かなしくなった。
I felt sad when a classmate treated me like I was some kind of vermin.
ばい菌きんを殺ころすto kill germs
このスプレーはばい菌きんを殺ころす効こう果かがある。
This spray is effective at killing germs.
ばい菌きんがうつるfor germs to spread or be transmitted
傷きず口ぐちからばい菌きんがうつることがある。
Germs can spread through an open wound.

Kanji

菌germ, fungus, bacteria
黴mold, mildew

Related words

細さい菌きんN2sense 1
細菌 is the neutral, scientific term for bacteria, while ばい菌 is the everyday word people use when talking about dirtiness or infection.
雑ざっ菌きん sense 1
雑菌 refers to miscellaneous unwanted bacteria or contaminants, while ばい菌 is the simpler, more childlike word used in everyday hygiene talk.
病びょう原げん菌きん sense 1
病原菌 specifically means a disease-causing microorganism, whereas ばい菌 is a broader, more colloquial term that doesn't require an actual illness.
菌きんN2
ばい菌 is a casual, everyday word for harmful germs (often used with children), while 菌 is the neutral, scientific term.

Don't confuse with

ウイルスN3sense 1
ウイルス refers specifically to viruses, a different kind of microorganism from the bacteria that ばい菌 usually implies, though both get blamed for sickness in casual speech.
カビN3
黴菌 shares the kanji 黴 with カビ but is a general colloquial word for germs or bacteria, whereas カビ refers specifically to visible mold or mildew.

Written forms

ばい菌きんUsage33%
Common mixed-kana spelling and the high-priority form.
バイキンUsage33%
search-only kana form
Search-only katakana form; can appear in emphatic or child-facing contexts but is not the main dictionary spelling.
バイ菌きんUsage19%
search-only kanji form
Search-only mixed katakana form; may be useful for lookup but is not the standard spelling.
黴ばい菌きんUsage7%
Full-kanji spelling; understandable but less common and visually heavier than ばい菌.
ばいきんUsage7%

Etymology

The full kanji spelling 黴菌 combines 黴, associated with mold, and 菌, associated with fungi, bacteria, or germs. The common written form ばい菌 replaces the difficult first kanji with kana.