Final answer:
In Laurie Halse Anderson's Speak, 'IT' is a term used by Melinda Sordino for Andy Evans, the person who assaulted her, as a form of depersonalization and coping.
Step-by-step explanation:
In the book Speak by Laurie Halse Anderson, 'IT' refers to Andy Evans, the character who sexually assaulted the protagonist, Melinda Sordino. Melinda calls him 'IT' as a way of depersonalizing and dissociating from the traumatic event. This terminology reflects her struggle to process the assault and the pain associated with the individual responsible. The use of 'IT' instead of a name can act as a protective mechanism to mentally distance herself from the trauma and as a way to avoid speaking his name, which could evoke further distress.