Formal:
* Amour secret: This is the most direct and literal translation. It emphasizes the secrecy of the love.
* Amour caché: This translates to "hidden love" and implies that the love is being kept concealed.
Informal:
* Amour interdit: This means "forbidden love" and suggests that the love is against societal norms or rules.
* Amour clandestin: This translates to "clandestine love" and implies that the love is kept secret and carried out in secret.
* Amour en cachette: This means "love in hiding" and emphasizes the secrecy of the relationship.
Poetic:
* Un amour impossible: This means "an impossible love" and adds a touch of drama and longing to the expression.
* Un amour sans nom: This translates to "a nameless love" and suggests a love that cannot be spoken aloud.
The best way to choose the right phrase depends on the context and the specific meaning you want to convey.