flu /fluː/ noun [uncountable]
[Date: 1800-1900; Origin: influenza]
a common illness that makes you feel very tired and weak, gives you a sore throat, and makes you cough and have to clear your nose a lot Synonym : influenza:
Steven’s still in bed with flu.
She’s got the flu.
I couldn’t go because I had flu.
a flu virus/bug
the spread of the flu virus
Doctors now fear a flu epidemic.

[TahlilGaran] Dictionary of Contemporary English ▲

flu
noun
ADJ. mild | gastric | summer
QUANT. bout, dose She's had a nasty dose of flu.
VERB + FLU be in bed with, be laid up with, have, suffer from | catch, contract, get, go down with
FLU + NOUN bug, virus | epidemic | victim | vaccine | jab
 ⇒ Special page at ILLNESS

[TahlilGaran] Collocations Dictionary ▲

flu
noun
BAD: I think I have caught a flu.
GOOD: I think I have caught (the) flu.

Usage Note:
flu or the flu (NOT a flu ): 'They are both off work with flu.' 'Even our doctor is down with the flu.'

[TahlilGaran] Dictionary of Common Errors ▲