William David Labov, a former professor of linguistics in the School of Arts & Sciences and a widely recognized pioneer in the field of sociolinguistics, died on December 17, 2024 from complications of Parkinson’s Disease. He was 97.

Dr. Labov was born in Passaic, New Jersey, and grew up in Rutherford and Fort Lee, New Jersey. He attended Harvard University, where he majored in English and philosophy and studied chemistry; he graduated in 1948. After graduating from Harvard, Dr. Labov worked as an industrial chemist in his family’s business from 1949 to 1961 before turning to linguistics and pursuing an MA at Columbia University. His master’s thesis (1962), now considered a founding document of sociolinguistics, examined the regional dialect of Martha’s Vineyard, Massachusetts, and the social status it conferred. He earned a PhD from Columbia in 1964, studying under renowned Jewish-American linguist Uriel Weinreich, and spent the rest of the 1960s as an assistant professor of linguistics at Columbia.

In 1969, Dr. Labov joined Penn’s faculty as a professor of linguistics in the School of Arts & Sciences, a position he would hold until his retirement in 2014. Beginning with his book The Social Stratification of English in New York City (1966), which contained the first serious study of Puerto Rican speech patterns in New York, Dr. Labov argued that regional and urban English dialects, even ones considered uncouth, were valid accents that merited study. In the early 1970s, he was one of the first academic researchers to study African American Vernacular English (AAVE), and he taught classes at Penn wherein students tutored young children in West Philadelphia schools and churches, simultaneously learning about the dialects these children spoke. In 1972, Dr. Labov published the book Language in the Inner City: Studies in Black English Vernacular about this work. In 1979, Dr. Labov testified in favor of Black students in Ann Arbor, Michigan, in a federal lawsuit they brought against their elementary school alleging a language barrier between teachers and students.

Dr. Labov was also a technological innovator: His early research involved the then-innovative approach of recording his subjects and analyzing their speech on a computer, a technique that was taken up by other researchers during the 1970s. He was also an early adopter of the Python programming language, using it to decode speech patterns. During the 1980s, he worked on overcoming dialect barriers by co-writing graphic novels that were written in standard English but discussed themes relevant to urban children. Later, Dr. Labov studied vowel chain shifts, eventually writing Principles of Linguistic Change (1994) and co-authoring the Atlas of North American English (2006) about regional variations in vowel sounds.

Dr. Labov mentored several students who went on to become renowned linguists themselves. “His unfailing patience, kindness, and generosity provided a model for the generations of linguists he trained here, many of whom have gone on to become highly influential linguists in their own right,” said his former student Meredith Tamminga, an associate professor and graduate chair of linguistics at Penn. The Franklin Institute awarded Dr. Labov the 2013 Benjamin Franklin Medal in Computer and Cognitive Science. In 2020, he received the Talcott Parsons Prize from the American Academy of Arts and Sciences. He continued to conduct and publish research after his retirement from Penn.

Dr. Labov is survived by his wife, Gillian Sankoff; his seven children, Susannah Page, Sarah Labov, Simon Labov, Joanna Labov, Jessie Labov, Alice Goffman, and Rebecca Labov; and nine grandchildren. He was previously married to the late Teresa Gnasso.