This Op-Doc tells the story of Marie Wilcox, the last fluent speaker of the Wukchumni language, and the dictionary she has created. I met her through the Advocates for Indigenous California Language Survival, an organization that encourages the revival of languages like Wukchumni. Through training and mentorship, it has supported Ms. Wilcox’s work for several years. Ms. Wilcox’s tribe, the Wukchumni, is not recognized by the federal government. It is part of the broader Yokuts tribal group native to Central California. Before European contact, as many as 50,000 Yokuts lived in the region, but those numbers have steadily diminished. Today, it is estimated that fewer than 200 Wukchumni remain.