Ehretia anacua is medium-sized tree found in eastern Mexico and southern Texas in the United States. It is a member of the borage family, Boraginaceae. One of its common names, anacua, is derived from the Mexican Spanish word anacahuite, as is that of the related Cordia boissieri, the anacahuita. That word in turn is derived from the Nahuatl words āmatl, meaning "paper," and quatitl, meaning "tree," possibly referring to the bark. It is also known as knockaway, a corruption of anacua, and sandpaper tree.