Kanji are the Chinese characters used in the Japanese writing system. It is one of the 3 scripts used in the Japanese language. The other two scripts are hiragana and katakana. Kanji are ideograms, graphic symbols that correspond to ideas or that represent words.
The first kanji character above is pronounced Tang in Chinese Mandarin. This refers to the Tang Dynasty, one of China's most prosperous eras. It can be pronounced to or kara in Japanese and was used in reference to China or things having to do with China. The second character is pronounced shou in Mandarin, or te in Japanese, and it means "hand." Together, these symbols form the words "China hand." Although these characters were originally pronounced as tode, they later became pronounced as karate, still meaning "China hand." The word karate became the popular term to describe this Okinawan system of unarmed self defense that had been influenced by the martial arts of China.
kara or to
"Tang" or "China"
In the early 1900's, the kanji symbol for China was replaced with another one. The new character is pronounced kong in Mandarin. In Japanese, it is pronounced kara and means "empty." Although this martial art was still called karate, it now had a different translation. Instead of meaning "China hand", it now meant "empty hand." This gave reference to the idea of defending oneself without weapons as well as to the notion of emptying one's mind of all impure thoughts. Of course, this also helped karate to conform to Japanese nationalism by avoiding any association of the art of karate with China.
The first known document to reflect the change in karate's meaning appeared in Chomo Hanashiro's book Karate Kumite, first published in August 1905. Hanashiro, a great karate master, was a student of Bushi Matsumura and later, Anko Itosu. Hanshiro used the kanji characters for "Empty Hand" in the title of his book.