xìjūn: 细菌 - Bacteria, Germs

• Keywords: 细菌, xijun, bacteria in Chinese, germs in Chinese, microbe, virus vs bacteria Chinese, wash your hands in Chinese, microbiology, Chinese for germ, Chinese for bacteria, HSK 5 vocabulary.
• Summary: Learn the essential Chinese word for bacteria and germs, 细菌 (xìjūn). This guide breaks down its meaning, character origins, and practical use in everyday conversations about health, hygiene, and sickness. Discover how to talk about 'good bacteria' versus 'bad bacteria' and understand its cultural context in modern China, from telling kids to wash their hands to discussions about food safety. This entry is perfect for beginners wanting to expand their practical vocabulary for daily life.

• Pinyin (with tone marks): xìjūn
• Part of Speech: Noun
• HSK Level: HSK 5
• Concise Definition: A single-celled microorganism; a bacterium or germ.
• In a Nutshell: 细菌 (xìjūn) is the common, everyday word for “bacteria” in Chinese. However, in casual conversation, it's often used as a catch-all term for “germs”—any tiny organism that can make you sick. It’s the word a parent would use to tell their child to wash their hands before eating. While it has a specific scientific meaning, think of its general usage as very similar to the English word “germs.”

• 细 (xì): This character means “fine,” “thin,” “slender,” or “minute.” The character is composed of the silk radical (纟) and the character for field (田). Imagine fine silk threads, emphasizing something very small and detailed. It gives the sense of something microscopic.
• 菌 (jūn): This character means “fungus,” “mushroom,” or “germ.” The top part is the “grass radical” (艹), which is used in many characters related to plants or plant-like life. The bottom part (囷) is a phonetic component that originally depicted a round granary, perhaps hinting at the shape or clustering nature of these organisms.

When combined, 细菌 (xìjūn) literally translates to “minute fungi/germs,” an apt description for bacteria.

While 细菌 (xìjūn) is a scientific term, its usage is deeply embedded in modern China's focus on public health and hygiene.

• Hygiene as a Modern Value: Following major public health events like SARS and COVID-19, awareness of germs and transmission has become a significant part of daily life. Public service announcements, signs in restrooms, and parental advice frequently use the word 细菌 to encourage behaviors like hand-washing (洗手, xǐshǒu) and using serving chopsticks (公筷, gōngkuài).
• Comparison to “Germs”: The most useful comparison for an English speaker is the word “germs.” In a scientific setting, English speakers differentiate between bacteria, viruses, and fungi. But in casual speech, a parent might say, “Don't eat that, it's full of germs!” without specifying the type of microbe. 细菌 (xìjūn) functions in the same way in casual Chinese. While it technically means “bacteria,” people often use it to refer to any unseen, illness-causing microbe. In a medical context, however, the distinction between 细菌 (xìjūn) and 病毒 (bìngdú - virus) is crucial and strictly maintained.

细菌 is a high-frequency word used in various contexts, almost always related to health and cleanliness.

• In Daily Conversation: It's most often used with a negative connotation, referring to harmful germs. You'll hear it constantly in discussions about food safety, personal hygiene, and cleaning.
  • “Remember to wash your hands, they're covered in germs!” (记得洗手，手上都是细菌！)
• In Medical Settings: Doctors use it to specify a “bacterial infection” (细菌感染, xìjūn gǎnrǎn) as opposed to a “viral infection” (病毒感染, bìngdú gǎnrǎn). This is critical because it determines the treatment (e.g., antibiotics for bacteria).
• In a Positive Context: While less common, it can be used positively when discussing beneficial bacteria, such as probiotics. In this case, it's often paired with characters like 益 (yì - beneficial) or 好 (hǎo - good).
  • “Yogurt contains a lot of beneficial bacteria.” (酸奶里含有很多有益细菌。)

• Example 1:
  • 吃饭前要洗手，不然会把细菌吃进肚子里。
  • Pinyin: Chīfàn qián yào xǐshǒu, bùrán huì bǎ xìjūn chī jìn dùzi lǐ.
  • English: You must wash your hands before eating, otherwise you'll eat germs.
  • Analysis: A classic, common sentence used by parents and teachers. 把 (bǎ) is used here to show the disposal of the object 细菌 (xìjūn) into the stomach.
• Example 2:
  • 医生说我的喉咙痛是细菌感染引起的。
  • Pinyin: Yīshēng shuō wǒ de hóulóng tòng shì xìjūn gǎnrǎn yǐnqǐ de.
  • English: The doctor said my sore throat was caused by a bacterial infection.
  • Analysis: This shows the standard medical use of the term, paired with 感染 (gǎnrǎn), meaning “infection.”
• Example 3:
  • 这个消毒液可以杀死99%的细菌。
  • Pinyin: Zhège xiāodú yè kěyǐ shā sǐ bǎi fēn zhī jiǔshíjiǔ de xìjūn.
  • English: This disinfectant can kill 99% of bacteria.
  • Analysis: A common phrase from advertisements for cleaning products. 杀死 (shā sǐ) means “to kill.”
• Example 4:
  • 酸奶里含有很多对肠道有益的细菌。
  • Pinyin: Suānnǎi lǐ hán yǒu hěnduō duì chángdào yǒuyì de xìjūn.
  • English: Yogurt contains a lot of bacteria that are beneficial for the gut.
  • Analysis: This is a great example of 细菌 used in a positive context. 有益的 (yǒuyì de) means “beneficial.”
• Example 5:
  • 食物在夏天容易滋生细菌，所以要放进冰箱。
  • Pinyin: Shíwù zài xiàtiān róngyì zīshēng xìjūn, suǒyǐ yào fàng jìn bīngxiāng.
  • English: Food easily breeds bacteria in the summer, so it needs to be put in the refrigerator.
  • Analysis: 滋生 (zīshēng) is a formal verb meaning “to breed” or “to multiply,” and it's frequently used with 细菌.
• Example 6:
  • 这不是细菌问题，是病毒引起的感冒。
  • Pinyin: Zhè bùshì xìjūn wèntí, shì bìngdú yǐnqǐ de gǎnmào.
  • English: This isn't a bacterial problem, it's a cold caused by a virus.
  • Analysis: This sentence directly highlights the crucial distinction between 细菌 (xìjūn) and 病毒 (bìngdú).
• Example 7:
  • 他因为伤口被细菌感染而发高烧。
  • Pinyin: Tā yīnwèi shāngkǒu bèi xìjūn gǎnrǎn ér fā gāoshāo.
  • English: He has a high fever because his wound was infected by bacteria.
  • Analysis: The passive voice marker 被 (bèi) is used here to show the wound was acted upon by the bacteria.
• Example 8:
  • 用显微镜才能看到微小的细菌。
  • Pinyin: Yòng xiǎnwēijìng cái néng kàn dào wēixiǎo de xìjūn.
  • English: You can only see the tiny bacteria by using a microscope.
  • Analysis: A scientific context. 显微镜 (xiǎnwēijìng) means “microscope.”
• Example 9:
  • 保持厨房卫生是防止细菌传播的关键。
  • Pinyin: Bǎochí chúfáng wèishēng shì fángzhǐ xìjūn chuánbò de guānjiàn.
  • English: Maintaining kitchen hygiene is the key to preventing the spread of germs.
  • Analysis: This sentence connects 细菌 to the broader concept of 卫生 (wèishēng - hygiene).
• Example 10:
  • 抗生素只对细菌有效，对病毒无效。
  • Pinyin: Kàngshēngsù zhǐ duì xìjūn yǒuxiào, duì bìngdú wúxiào.
  • English: Antibiotics are only effective against bacteria, not against viruses.
  • Analysis: A very practical and important sentence that clarifies the function of antibiotics (抗生素, kàngshēngsù).

• 细菌 (xìjūn) vs. 病毒 (bìngdú): This is the most critical distinction for learners to master.
  • 细菌 (xìjūn) = Bacteria. Treatable with antibiotics (抗生素, kàngshēngsù). Examples: Strep throat, bacterial pneumonia.
  • 病毒 (bìngdú) = Virus. Not treatable with antibiotics. Examples: Common cold (感冒, gǎnmào), the flu (流感, liúgǎn).
  • Common Mistake: Saying you have a cold (感冒) because of 细菌. This is scientifically incorrect and sounds unnatural to a native speaker.
  • Incorrect: 我感冒了，因为我接触了细菌。 (Wǒ gǎnmào le, yīnwèi wǒ jiēchù le xìjūn.)
  • Correct: 我感冒了，因为我感染了病毒。 (Wǒ gǎnmào le, yīnwèi wǒ gǎnrǎn le bìngdú.)
• Over-generalization: While Chinese speakers use 细菌 casually like “germs,” avoid using it in a medical context unless you are sure it's a bacterial issue. If you are unsure what is causing an illness, it's better to use a general term like 生病了 (shēngbìng le - got sick).

• 病毒 (bìngdú) - Virus. The most important counterpart to 细菌. One causes bacterial infections, the other causes viral infections.
• 微生物 (wēishēngwù) - Microorganism. The broader, scientific category that includes both bacteria and viruses.
• 消毒 (xiāodú) - To disinfect, to sterilize. The action one takes to kill 细菌.
• 感染 (gǎnrǎn) - Infection. The state of being invaded by harmful microorganisms like 细菌.
• 抗生素 (kàngshēngsù) - Antibiotics. The medicine specifically used to fight 细菌.
• 益生菌 (yìshēngjūn) - Probiotics. A term for beneficial bacteria, often found in yogurt and health supplements. Literally “beneficial living fungi/germs.”
• 卫生 (wèishēng) - Hygiene, sanitation. The practice and condition of maintaining health and preventing disease by keeping clean.
• 免疫力 (miǎnyìlì) - Immunity. The body's ability to resist infection by 细菌 and other pathogens.
• 发炎 (fāyán) - To become inflamed. A common symptom of a 细菌 infection.