Opaque literally means "not transparent" or "impenetrable to light". It's a less common word in everyday conversation, making it stand out in song lyrics.
In this song, Zaho uses it metaphorically to describe her emotional state: "Oui j'ai le cœur opaque" (Yes, I have an opaque heart). This powerful image suggests her heart is closed off, perhaps due to pain or hurt, making it difficult for others to see or understand her true feelings. It's a poignant way to express emotional guardedness.
In "Les Mots" (The Words), Zaho sings about a relationship strained by past hurts and a breakdown in communication. The singer feels her partner wants her to leave because they can't change the past. She describes a deep sadness, feeling attacked and becoming defensive, her heart growing "opaque." Despite the conflict, she still loves her partner, even if it's a secret or unacknowledged love ("je t'aime au black").
The central theme is the power and failure of words. The singer wishes she had the right words to heal her partner's pain ("Si j'avais les mots... Pour soigner tes maux"). She reflects on their shared history, acknowledging her own mistakes and that her hatred is now "obsolete." The song suggests that focusing too much on finding faults will inevitably create them, and questions whether physical distance ("Loin des yeux, loin du cœur") can truly solve their emotional problems.