Final answer:
Mercutio gives Romeo the "Queen Mab Speech" in Romeo and Juliet.
Step-by-step explanation:
The speech that Mercutio gives to Romeo in Shakespeare's play Romeo and Juliet is called the Queen Mab Speech. Mercutio delivers this speech in Act I, Scene 4 of the play. In the speech, Mercutio describes Queen Mab, a fictional fairy who is believed to be responsible for causing dreams.