Donna Jo Napoli (born February 28, 1948) is an American writer of children's and young adult fiction, as well as a prominent linguist. She has worked in syntax, phonetics, phonology, morphology, historical and comparative linguistics, Romance studies, the structure of Japanese, structure of American Sign Language, poetics, writing for ESL students, and mathematical and linguistic analysis of folk dance. She has taught linguistics at Smith College, the University of North Carolina at Chapel Hill, Georgetown University, the University of Michigan at Ann Arbor, the University of Pennsylvania, and is currently a professor of linguistics and social justice at Swarthmore College.