On'yomi

On'yomi (音読み, [oɰ̃jomi], lit. "sound(-based) reading"), or the Sino-Japanese reading, is the reading of a kanji based on the historical Chinese pronunciation of the character. A single kanji might have multiple on'yomi pronunciations, reflecting the Chinese pronunciations of different periods or regions. On'yomi pronunciations are generally classified into go-on, kan-on, tō-on and kan'yō-on, roughly based on when they were borrowed from China.

Generally, on'yomi pronunciations are used for technical, compound words, while the native kun'yomi pronunciation is used for singular, simpler words.