Gairaigo

Gairaigo (外来語^?) is Japanese for "loan word" or "borrowed word", and indicates a transliteration (or "transvocalization") into Japanese. In particular, the word usually refers to a Japanese word of foreign origin that was not borrowed in ancient times from Old or Middle Chinese, but in modern times, primarily from English or from other European languages. These are primarily written in the katakana phonetic script, with a few older terms written in Chinese characters (kanji); this latter is known as ateji.

Japanese has a large number of loan words from Chinese, accounting for a sizeable fraction of the language. These words were borrowed during ancient times and are written in kanji. Modern Chinese loanwords are generally considered gairaigo and written in katakana, or sometimes written in Chinese and glossed with katakana furigana; pronunciation of modern Chinese loanwords generally differs from the corresponding usual pronunciation of the characters in Japanese.

For a list of terms, see the List of gairaigo and wasei-eigo terms.

Japanese has a long history of borrowing foreign languages. It has been borrowing foreign languages since late fourth century AD to recent years. Some ancient "gairaigo" words are still being used nowadays, but there are also many kind of "gairaigo" words borrowed currently from foreign countries.

Most, but not all, modern gairaigo are derived from English, particularly in the post-World War II era (after 1945). Words are taken from English for concepts that do not exist in Japanese, but also for other reasons, such as a preference for English terms or fashionability – many gairaigo have Japanese synonyms.

In the past, more gairaigo came from other languages besides English. The first period of borrowing foreign language occurred during the late fourth century AD, when a massive amount of Chinese characters were adopted. This period could be considered as one of the most significant history of "gairaigo", because it was the first moment when the written communication system, such as Kanji and Hiragana, were formed.

...
Wikipedia