This type of word is one that is taken from one language and used in another without translation, demonstrating a lexical vacuum in the latter.
What is the difference between a foreign word and a loan word? A foreign word tends to, at first, remain unchanged and then undergo a phonetic and morphological adaptation. With regards to a loan word, when the incorporation is done due to a linguistic gap in the recipient language, constitutes a form of enrichment of the language. Hispanisations, for example, are more tolerated in a text that is read as though it is not a translation.
Foreign words and expressions must be handled with caution, since it is very easy to be perceived as superfluous by the reader. Let us work to avoid them, whenever possible.
As translators, we use foreign words and loans to lend a hint of local flavor to the text. We apply it, in moderation, to measurements, treatments, currencies, and other elements of specific cultural content.
If a foreign word is used, it is important to verify that it is spelled correctly. It is possible that in the process of importation, new meanings were introduced.