Extremely calm, relaxed and in control of one’s emotions
I don’t understand how you can stay cool as a cucumber when you give presentations to more than 100 people. I get so nervous and I always mix up my words.
This phrase may have originated from the fact that even in hot weather, the inside of cucumbers are approximately 20 degrees cooler than the outside air. Cool and crisp, the cucumber belongs to the same family as pumpkins and watermelons. It was one of the earliest vegetables to be cultivated.
The belief is ancient, but was first put on record by Francis Beaumont and John Fletcher in their play Cupid’s Revenge (1610), when they referred to certain women as «as cold as cucumber».
Therefore, a person who stays cool, calm and relaxed in a difficult situation can be compared to a cucumber staying cool inside, even in hot weather!
Être frais comme un concombre
Correct French idiom
Faire preuve d’un calme olympien