DIVA'S BIG MOMENT is a term used to describe the moment when a singer performs a SOLO or an ARIA in an opera. It is a moment of great importance for the singer, as it is their chance to showcase their vocal talent and to captivate the audience. The two crossword solutions for this term are SOLO (4 letters) and ARIA (4 letters). A SOLO is a piece of music performed by one singer, while an ARIA is a type of SOLO that is usually found in operas.