Definition of membrane

The word "membrane" has its roots in Latin. The Latin word "membrana" means "skin" or "hide," and it is derived from the verb "membrare," which means "to skin" or "to strip." This verb is also related to the Latin word "membrum," meaning "limb" or "member," which refers to the idea of peeling or stripping away the outer layer of skin. The term "membrane" was borrowed into Middle English from Old French, where it was spelled "membrane." It initially referred to the thin, flexible layer of skin that covers the tongue, but later came to be applied to any thin, flexible sheet-like structure, such as the skin of a placenta or the lining of a cell. Today, the word "membrane" is used in biology, medicine, and engineering to describe a wide range of structures that separate or enclose spaces or compartments.