secret
In French, the word 'secret' is used in the same way as in English. It refers to something that is not known or seen by others, often because it is deliberately concealed. It can be used as an adjective or a noun, and is a common word in everyday language.
I am going to tell you a secret.
This sentence uses the word 'secret' in a very straightforward manner. It implies that the speaker is about to share a hidden piece of information with the listener, typically something not known by many people.
She kept the secret for years.
In this sentence, 'secret' refers to a piece of information that has been withheld by the subject, 'Elle', for a considerable length of time, in this case, years. This usage suggests a long-standing act of concealment.
It's an open secret.
This phrase refers to something that is widely known despite attempts to keep it secret. 'Secret de Polichinelle' is a common idiomatic phrase in French used to describe such situations, akin to the English term 'open secret'.