A loanword (also loan word or loan-word) is a word adopted from one language (the donor language) and incorporated into another language without translation.
A loanword is distinguished from a calque (loan translation), which is a word or phrase whose meaning or idiom is adopted from another language by translation into existing words or word-forming roots of the recipient language.
Examples of loanwords in the English language include café (from French café, which literally means "coffee"), bazaar (from Persian bāzār, which means "market"), and kindergarten (from German Kindergarten, which literally means "children's garden").
In a bit of heterological irony, the word calque is a loanword from the French noun, derived from the verb calquer (to trace, to copy); the word loanword is a calque of the German word Lehnwort; and the phrase "loan translation" is a calque of the German Lehnübersetzung.
Loans of multi-word phrases, such as the English use of the French term déjà vu, are known as adoptions, adaptations, or lexical borrowings.
Strictly speaking, the term loanword conflicts with the ordinary meaning of loan in that something is taken from the donor language without it being something that is possible to return.
Most of the technical vocabulary of classical music (such as concerto, allegro, tempo, aria, opera, and soprano) is borrowed from Italian, and that of ballet from French.