infectious
gb/ɪnfˈɛkʃəs/ us/ɪnfˈɛkʃəs/
B2
Anglais
~ 8900
Sens
0 sens
adjective
B2
property
1
able to spread between people
Describes a disease or germ that can move from one person or animal to another.
Schéma d’usage :
[disease/condition] is infectious; an infectious [disease/virus]
Erreur fréquente :
Learners often confuse "infectious" with "infected". "Infectious" describes something that can pass an illness to others (an infectious disease, an infectious person), while "infected" describes someone or something that already has the illness (an infected wound, an infected patient). Learners also mix up "infectious" and "contagious"; in everyday speech they overlap, but "infectious" is slightly more technical.
Synonymes
contagious (Very common everyday word for diseases that easily pass from person to person; often slightly less technical than "infectious".)
Antonymes
noninfectious (Used especially in medical or scientific contexts for diseases that cannot be spread from one person to another.)
Collocations
highly infectious
|infectious disease
|infectious virus
|infectious patient
|become infectious
|remain infectious
Thèmes
health
|science
Exemples
- Measles is one of the most infectious diseases known.
- Patients are most infectious in the first few days after symptoms appear.
- The virus is highly infectious and spreads quickly in crowded spaces.
- Health workers wore masks and gloves while treating infectious patients.
- Public health officials are worried about a new infectious strain of the virus.
Exemples pédagogiques
- The flu is very infectious.
- He stayed at home because he was still infectious.
- Some viruses are more infectious than others.
- Doctors try to keep infectious people away from other patients.
- The disease became less infectious after a few weeks.
adjective
technical
C1
property
2
caused by infection (medical)
Describes a disease or problem in the body that happens because germs enter and grow in it, not because of injury or birth problems.
Schéma d’usage :
infectious [disease/condition/cause/etiology]
Erreur fréquente :
Learners may not see the difference between an "infectious" disease (caused by infection) and one that is simply "serious" or "dangerous". Another confusion is between diseases that are infectious but not easily spread and those that are easily passed on (highly infectious or highly contagious).
Synonymes
infective (More technical and less common; used mostly in medical and scientific writing for conditions or agents related to infection.)
Antonymes
noninfectious (Used in contrast to describe diseases or conditions that are not caused by infection, such as genetic or degenerative diseases.)
Collocations
infectious disease specialist
|infectious etiology
|infectious agent
|infectious cause
|infectious process
|infectious origin
Thèmes
health
|science
Exemples
- The patient’s fever was due to an infectious rather than an autoimmune cause.
- She decided to specialize in infectious diseases during her medical training.
- The study compares infectious and noninfectious causes of liver failure.
- Public health policies differ for infectious and noninfectious conditions.
- They ruled out an infectious process after all cultures came back negative.
Exemples pédagogiques
- Doctors are worried about new infectious diseases.
- He works as an expert in infectious diseases at the hospital.
- Some heart problems are infectious, and some are not.
- The report says the lung problem is infectious, not genetic.
- They are studying infectious causes of eye problems.
adjective
B2
property
3
spreading emotions or behavior
Describes a feeling or way of acting that makes other people feel or act the same way.
Schéma d’usage :
infectious [laughter/smile/enthusiasm/energy]
Erreur fréquente :
Learners sometimes think "infectious" can only describe diseases. In modern English it is very common to describe positive feelings or behavior as "infectious", especially laughter, enthusiasm, or energy. It is not used for all emotions; for example, "infectious anger" is possible but much less common than "infectious joy" or "infectious excitement".
Synonymes
contagious (Very common figurative synonym for moods and behaviors that spread quickly; slightly more informal in this emotional sense.)
Antonymes
uninspiring (Describes behavior or emotion that does not spread to others and does not make them feel the same way.)
Collocations
infectious laughter
|infectious smile
|infectious enthusiasm
|infectious energy
|infectious optimism
|infectious excitement
Thèmes
emotions
|social
Exemples
- Her infectious laughter made everyone in the room start giggling.
- His infectious enthusiasm motivated the whole team to work harder.
- The band’s infectious energy had the crowd dancing within minutes.
- There was an infectious sense of optimism at the start of the project.
- Her infectious smile put the nervous students at ease.
Exemples pédagogiques
- His infectious smile made me happy too.
- The teacher’s infectious energy helped the class stay awake.
- Her infectious laughter filled the small café.
- The child’s infectious joy spread to everyone around him.
- The singer’s infectious excitement made the show fun.
Grammaire
Forme canonique
infectious
API
GB/ɪnfˈɛkʃəs/
US/ɪnfˈɛkʃəs/
Syllabes et accentuation
in - fec - tious (3 syllabes)
Stress on 2nd syllable (fec)
Formes du mot
Adjective
- Base: infectious
Famille de mots
Related words
contagious
adjective B2
contagion
noun C1
Negative and opposite forms
noninfectious
adjective
disinfect
verb
disinfection
noun
disinfectant
noun
Advanced or less common
infective
adjective
infectiously
adverb
infectiousness
noun
Expressions
highly infectious
1/hˈaɪli ɪnfˈɛkʃəs/
fixed phrase
very easy to spread infection
Describes a disease or germ that spreads to other people very easily.
Exemples
- COVID-19 is a highly infectious respiratory illness.
- Because the virus is highly infectious, even short contact can be risky.
- Officials warned that the new variant is more highly infectious than earlier strains.
infectious disease
1/ɪnfˈɛkʃəs dɪzˈiz/
fixed phrase
disease spread by infection
A disease that can move from one person, animal, or organism to another because of germs.
Exemples
- The hospital has a special unit for patients with infectious diseases.
- Vaccination has greatly reduced deaths from many infectious diseases.
- Clean water and good hygiene help prevent infectious disease in poor areas.
infectious laughter
1/ɪnfˈɛkʃəs lˈæftɚ/
fixed phrase
laughter that spreads to others
Laughter that makes other people start laughing too.
Exemples
- Her infectious laughter broke the tension in the room.
- The comedian’s infectious laughter was almost funnier than his jokes.
- Children’s infectious laughter echoed through the park.