The nurse, who is not the most educated person in the world, commits a malapropism here. She uses the wrong word, but one that sounds like the word she intended. What the Nurse meant to say was, "I desire some conference with you," meaning she wants to speak to Romeo. Benvolio makes fun of her by intentionally committing another malapropism: he says that the nurse is going to "indite" Romeo to supper" instead of "invite" him.