chase: a rectangular metal frame used in letterpress printing to hold together the pages or columns of composed type that are printed at one time
frame: the framework for a pair of eyeglasses
mucus: protective secretion of the mucus membranes; in the gut it lubricates the passage of food and protects the epithelial cells; in the nose and throat and lungs it can make it difficult for bacteria to penetrate the body through the epithelium