Squamous metaplasia is a medical term used to describe a change in the type of cells in a particular tissue or organ. Some synonyms for squamous metaplasia include squamification, squamous transformation, and squamous differentiation. These terms all refer to the same process, which involves the transformation of a layer of cells from one type to another. Squamous metaplasia commonly occurs in areas of the respiratory tract that are exposed to irritants, such as cigarette smoke, air pollution, or dust. It is also seen in other tissues, such as in the uterus during pregnancy or in certain types of cancer.