Amarras literally translates to "moorings" or "ties", referring to the ropes or chains used to secure a ship. It's a less common word in everyday conversation, making it stand out.
In this song, the phrase "Solto as amarras" (I release the moorings) is a beautiful metaphor for letting go of inhibitions and constraints. It signifies a complete surrender to love and emotion, especially when the beloved is distant, emphasizing a profound longing and readiness to abandon everything for them.