ENGLISH
REFERENCE

mono

n. uncountable
C1 Advanced Oxford US //ˈmoʊnoʊ// UK //mˈɒnəʊ// mono Informal Slang

n. an illness that makes you feel very tired and gives you a sore throat for a long time. It is common among teenagers and young adults and spreads through saliva.

n. an infectious disease caused by the Epstein-Barr virus, characterised by extreme fatigue, fever, and swollen lymph nodes. Informal in register; the full medical term is infectious mononucleosis.


SIMPLE

He missed two weeks of school because he had mono.

CONTEXTUAL

After feeling exhausted for a month, the student went to the clinic and tested positive for mono.

COMPLEX

While mono is rarely dangerous for healthy individuals, the resulting fatigue can linger for months, significantly impacting a student's academic performance and social life during the recovery period.

Synonyms
Origin

From Yokutsan and Miwok –chi, a suffix that wandered freely across tribal names until it attached itself to the group later recorded as Mono; the neighbouring Monache retain the same element, suggesting a shared linguistic way-marker rather than a self-chosen label.

Usage

Typically used without an article ('he has mono') or with the definite article in specific contexts ('the mono she caught').

Pitfall

He has a monoHe has monoUnlike 'a cold' or 'a headache', mono is treated as an uncountable disease name and does not take an indefinite article.

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