A loanword is a word borrowed from one language into another. It is fully incorporated into the new language, taking on the new language’s phonology and orthography so that it is interpreted by most speakers as a native term. A loanword is typically, though not always, employed for a concept that is not native to the borrowing language, such as a plant or animal that did not exist in the area where the borrowing language originated.
Terms can be borrowed from one language into another in a variety of ways; to be a true loanword, a word must be simply borrowed without translation and made to conform to the borrowing language’s conventions of spelling and pronunciation. Another type of borrowing, known as a calque or loan translation, translates the borrowed term into the words of the borrowing language. For example, loanword itself is a literally translated calque of the German word Lehnwort.
A term that is used in a different language without any changes in spelling or pronunciation is simply a foreign word. An example is the English chauffeur, taken directly from French. An example of an English loanword from French, on the other hand, is music from the French musique.
Calques are characterized by translation of one or more element of the original term into the new language. In a full loan translation, every element is translated into native words; for example, the French gratte-ciel, literally “scrape-sky,” is borrowed from the English skyscraper. In a partial substitution, part of the original term is borrowed wholesale, while part is translated; i.e. German Showgeschäft (“show business”), which adds the English word show to the German word for “business.”
Some borrowings from other languages preserve none of the form of the foreign word, but only the meaning, attaching a foreign concept to a native term. For example, the native French term for “mouse,” souris, is now used to refer to a computer mouse, a concept borrowed from English.