Use Retin-A exactly as your doctor has prescribed it for you. Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended. Do not take by mouth. Retin-A is for use only on the skin.
Definition of wall for English Language Learners : a structure of brick, stone, etc., that surrounds an area or separates one area from another : the structure that forms the side of a room or building
A wall formed of two thicknesses of masonry with a space between them. Classified under: Nouns denoting man-made objects. Hypernyms (cavity wall is a kind of...): wall (an architectural partition with a height and length greater than its thickness; used to divide or enclose an area or to support another structure).