germ

germ — noun

1. one of the tiny organisms, like bacteria or viruses, that can get into a living

1.nounB1
Definition

one of the tiny organisms, like bacteria or viruses, that can get into a living body and cause illness or infection.

Example

Harper always washes her hands thoroughly after gardening to kill any germs.

collocation: kill germs / spread germs

The nurse explained that harmful germs can enter the body through a tiny cut on the skin.

Common collocations
  • kill germs
  • spread germs
  • carry germs
  • harmful germs
  • dangerous germs
  • get rid of germs
Synonyms
  • microbe

    more technical/scientific term for any microscopic organism, including non-disease-causing ones

  • bacterium

    specific type of germ; a single-celled organism, not a virus

  • virus

    specific type of germ; smaller than bacteria, needs a host cell to multiply

  • bug

    informal, very common in everyday English ('I caught a bug')

Usage Note

Usually appears in the plural form 'germs'. The singular is rare in everyday speech about illness — 'a germ' sounds more like a biology-class example than something a doctor would say.

Common Mistakes

I caught a germ from my classmate.
I caught a bug from my classmate.' or 'Germs spread easily at school.
'germ' is rare in singular form when talking about catching an illness; use 'bug' or rephrase with plural 'germs.'

2. the very first small sign or early stage of an idea, feeling, or quality that la

2.nounC1
Definition

the very first small sign or early stage of an idea, feeling, or quality that later develops into something bigger or more important.

Example

A brief chat with an elderly woman on a bus planted the germ of her novel.

fixed phrase: germ of an idea

Lucía spotted the germ of a good business plan scribbled in her brother's notebook.

Common collocations
  • germ of an idea
  • germ of a plan
  • germ of doubt
  • germ of truth
  • plant the germ of
  • contain the germ of
Synonyms
  • seed

    more common and slightly more versatile ('the seeds of change'), interchangeable in many contexts

  • origin

    broader; can refer to any starting point, not just an early, undeveloped one

  • embryo

    more formal/technical, often used in academic writing ('the embryo of a theory')

Antonyms

Grammar Patterns

the germ of [something]

Usage Note

Always used in the singular with 'of': 'the germ of an idea / a plan / doubt / truth'. The noun following 'germ of' must be abstract — never use it with concrete objects.

Common Mistakes

The germ of my new house was a small sketch.
The germ of my idea for a new house was a small sketch.
'germ of' must be followed by an abstract noun (idea, plan, doubt), not a concrete noun.

3. a small living structure inside a plant or animal — such as a seed's embryo or a

3.nounC1
Definition

a small living structure inside a plant or animal — such as a seed's embryo or a reproductive cell — that is capable of growing into a new organism or developing into a specific body part.

Example

Wheat germ, the nutrient-rich heart of the wheat seed, is often sprinkled onto breakfast cereal for extra vitamins.

compound noun: wheat germ

Baraka examined how germ cells divide and multiply during the earliest stages of an embryo's development.

term: germ cells

Common collocations
  • wheat germ
  • germ cell
  • germ layer
  • germ line
  • germ plasm
Synonyms
  • embryo

    more specific term for the early developmental stage of an animal; 'germ' is broader and also used for plants

  • seed

    refers to the whole reproductive unit of a plant; 'germ' is the part inside the seed that grows

  • bud

    used for new growth on plants; less technical than 'germ'

Usage Note

This is the original biological sense from which the other meanings of 'germ' developed. In modern biology, it appears in compound terms like 'wheat germ', 'germ cell', 'germ layer', and 'germ line'. Unlike sense 1, it does NOT refer to disease or illness.

Common Mistakes

Wheat virus is good for your health.
Wheat germ is good for your health.
'germ' in 'wheat germ' refers to the seed's embryo, not a disease-causing organism. Do not confuse with 'virus' or 'bacterium.'

Word family

  • germ-free
    adjectiveC1
  • germicide
    nounC2
  • germicidal
    adjectiveC2
  • germinate
    verbC1
  • germination
    nounC1

Synonym discussion

Sense: noun/1

All five words refer to tiny organisms or particles that can cause illness, but they differ in register, precision, and typical use. 'Germ' is the everyday, non-technical word for any disease-causing microorganism — the most natural choice in conversations about hand-washing, cleaning, or catching a cold. 'Microbe' is a broader scientific term covering all microscopic organisms, including harmless or beneficial ones (e.g., gut microbes); it sounds more clinical. 'Bacterium' and 'virus' name two specific biological categories: bacteria are single-celled organisms that can live independently, while viruses are much smaller and need a host cell to reproduce. 'Bug' is highly informal and conversational, used in phrases like 'I caught a bug' or 'a stomach bug.' In daily conversation, say 'germs' when talking about general illness prevention, and 'bug' when describing a specific illness you caught. In science class, use 'bacterium' or 'virus' for precision.

germ ↗microbe ↗bacteriumvirus ↗bug ↗

Etymology

LatinFrenchEnglish

The word 'germ' comes from the Latin 'germen,' meaning a sprout, bud, or offshoot. It entered English in the 1600s with the biological sense of a seed or embryo (today's sense 3). After Louis Pasteur and Robert Koch established the germ theory of disease in the late 1800s, the word gained its now-dominant meaning of a disease-causing microorganism (sense 1). The figurative use for abstract beginnings — 'the germ of an idea' — dates back to the early 1600s, originally drawing on the biological image of a seed about to sprout.