I recently discovered an interesting translation. Being ethnic Chinese and living and working in the Silicon Valley, I am constantly exposed to technology news in both English and Chinese. One night on the Cantonese news hour I saw the reporter referring to Oracle Corporation as 甲骨 in Chinese. Now, 甲 literally means "shell" and 骨 means "bone". Why would a high-tech software company be translated to this strange name (other than being reduced to bones after paying for their software and services (but I digress))?
Turns out an ancient Chinese script is the intermediary in this strange relationship. The earliest Chinese text were divinations carved on animal bones and turtle shells. These bones and shells were then subjected to heat to form cracks, which a priest would interpret to foretell the future. Because of this usage, Western scholars called this highly pictorial script Oracle Bone Script. However, in China the name of the script was instead 甲骨文, which translates as "shell (and) bone script".
This essentially created an equivalence between English "oracle bone" and Chinese 甲骨, despite the fact that the Chinese word doesn't really imply any kind of ritual divinatory function. Then by semantic shift, 甲骨 came to just mean "oracle" in the mind of the reporter who wrote the first Chinese news article on Oracle Corporation. From there on it entered common usage and eventually onto the news program I saw on television.
Semantic shifts like this happen quite frequently in the history of languages. For example, the word "kleenex" now practically means "soft paper tissue" but obviously it originated from the brand "Kleenex". What other such semantic shifts can you think of?