The British Idiom – Cool as a cucumber
Definition of Cool as a cucumber
If people describe you as cool as a cucumber then you are not the sort of person to get easily agitated or nervous about anything.
Examples of Usage of Cool as a cucumber
That James Bond character is as cool as a cucumber even when people are trying to kill him, and they often are. Even when the job interview was going badly I managed to stay as cool as a cucumber and got the job.
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