What word can refer to an English breed of edible fowl, as well as an extinct language of southwestern England?

The word you're looking for, which refers to both a type of edible fowl and an extinct language, is Cornish. This term directly links to Cornwall, a historic county located in the southwestern tip of England. The Cornish fowl, originally known as "Indian Game" chickens, was developed in this region around 1820. Breeders in Cornwall created this distinctive bird, known for its broad, muscular body and excellent meat quality, by crossing various game and Asiatic breeds. Today, the Cornish chicken is a foundational breed in the poultry industry, widely used in the production of fast-growing broiler chickens, particularly the popular Cornish Cross hybrid.

Coincidentally, "Cornish" also designates a Celtic language that was historically spoken by the people of Cornwall. This Brittonic language shares roots with Welsh and Breton, reflecting the region's ancient Celtic heritage. Over centuries, the spread of English led to a decline in Cornish speakers, and it eventually ceased to be a living community language by the late 18th or early 19th century. However, a dedicated revival movement began in the early 20th century, fueled by academic interest and a broader Celtic cultural resurgence. These efforts have been so successful that UNESCO reclassified the language from "extinct" to "critically endangered" in 2009 and 2010, recognizing the growing number of people learning and speaking Cornish today.

Thus, the word Cornish serves as a fascinating linguistic bridge, connecting a significant part of England's agricultural history with its unique cultural and linguistic past. It highlights how a regional identity can manifest in diverse ways, from a prized poultry breed to a revitalized ancestral tongue.