Karl van Duyn Teeter (March 2, 1929 – April 20, 2007) was an American linguist known especially for his work on the Algic languages.
Raised in Lexington, Massachusetts, he dropped out of high school and joined the United States Army, where he served as a Supply Sergeant from 1951 to 1954.
Teeter's work on Wiyot not only provided the last and best data for this language, but set the stage for the resolution of the Ritwan controversy.
Teeter not only provided crucial data, but recognized many of the correspondences with Algonquian cited by Mary Haas.
With field work on Wiyot no longer possible, Teeter turned his attention to Malecite-Passamaquoddy, a distantly related Algonquian language of New Brunswick and Maine.