bug · noun C /bʌg/Full view
bug (INSECT)
B1 a very small insect
Dictionary example:

He found a bug in his bed.

Learner example:

Maybe you're thinking that he's a loving man who talks only about bugs and insects, but it's not true. (Preliminary English Test; B1; Italian)

B2 a bacteria or a virus causing an illness that is usually not serious
Dictionary examples:

I had a stomach bug last week.

There's a bug going around.

B2 a mistake or problem in a computer program
Dictionary example:

A bug had caused the company's computer system to crash.

Learner example:

For instance, the millennium bug [might] make all computers confuse[d], and banks will lose money. (First Certificate in English; B2; Chinese)

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