Lip-reading is the skill, or the act, of understanding speech by watching someone’s lips when you cannot hear them well, or at all. It is the name that sits beside the verb lip-read: you practise lip-reading; a class may teach lip-reading. People use it in deaf education, in noisy rooms, and in films when a character watches a talk through glass. It is honest about the difficulty. You never catch every word. You catch enough, then fill the gaps from the face, the place, and what you already know.