William J. Gedney (April 4, 1915 – November 14, 1999) was an American linguist notable for his work on Thai and related Tai languages.

After graduation, Gedney lived in Leavenworth, Washington and worked as a high school English teacher.

During this period in New York he also began doctoral studies in Sanskrit at Yale University as a student of Franklin Edgerton.

He then moved to Thailand, where he studied Thai language and literature, working with some of the most important scholars of the country.

In his early years at Michigan, he helped develop the first Thai language training program for the Peace Corps.

He was known for the accuracy of his notes on the tonal and phonological characteristics of these languages, and developed important word lists and representations for the study and comparisons of their tone.