"Gesundheit!" Where did that word come from? It's English, isn't it? Most people know the word and how to use it, but few realize that it is actually a borrowed word, coming from German. The word is the normal word in German for "health." We use it as a kind of involuntary reaction to someone sneezing, but it really is a kind of blessing on the one who sneezed, a wish that they would not be sick, but be in health. You will find the word in almost every English dictionary, even though it is originally not an English word. We borrowed it.
What does this have to do with Bible translation? Borrowing words from one language to another is very normal for all languages, much more normal than "a cup of sugar." Words are either borrowed directly, like "Gesundheit," or they go through changes to adapt to their new home, like the word "woodchuck." A woodchuck does not "chuck wood" at all. The word comes from Algonquin, a native American language. Their word for the animal in question is "wuchak," which actually means "whistler," what the animal does when it senses danger. The trip from "wuchak" to "woodchuck" is a linguistic journey of change and adaptation that makes the borrowed word hardly recognizable any more as a borrowed word.
When we help translators find words in their language for ideas and concepts that are new to their culture and language, many times the translators need to borrow a word from a neighboring language. ("Could I borrow a cup of words?") Many Songhay words for spiritual things in Mali are actually Arabic words, such as "Almasihu" for "Messiah" (Christ). But some words don’t work, even if they look good at the start. The Songhay word "sheitan" looked like it would work for "Satan," but the word means "demon" instead. We had to come up with another word for Satan. The ethnic identity of a word can affect whether to use it or not. The Luxembourgish translators often have to choose between a word borrowed from French or a word borrowed from German, knowing that the region of the small country close to Germany will not like the French borrowed word as much, and vice versa. (By the way, "vice versa" is something we borrowed from Latin!)
A borrowed word must be true in two ways: its meaning and its identity. First, it must match the meaning of the word or words in the original language we are trying to translate, and that meaning must be easily known to the speakers of the language. Second, it must be recognizable as a word the language group accepts as their own, no matter what the origin may be. If the word suggests foreignness, then the people may fail to identify the translation as their own, and therefore find it interesting perhaps, but not actually their language. If it's something borrowed, it must also be something true.