section_path: Literacy and lexicography/Dictionaries
section_name: Dictionaries
paragraph_text: Dictionaries
  
  According to analyses of mainland Chinese, Taiwanese, Hong Kong, Japanese, and Korean sources, the total number of characters in the modern lexicon is around 15 000. Dozens of schemes have been devised for indexing Chinese characters and arranging them in dictionaries, though relatively few have achieved widespread use. Characters may be ordered according to methods based on their meaning, visual structure, or pronunciation.
  
  The Erya (c. 3rd century BCE) organised the Chinese lexicon into 16 semantic categories, as well as 3 describing abstract characters such as grammatical particles. The Shuowen Jiezi (c. 100 CE) introduced what would ultimately become the predominant method of organisation used by later character dictionaries, whereby characters are grouped according to certain visually prominent components called radicals (部首; bùshǒu; ' section headers '). The Shuowen Jiezi used a system of 540 radicals, while subsequent dictionaries have generally used fewer. The set of 214 Kangxi radicals was popularised by the Kangxi Dictionary (1716), but originally appeared in the earlier Zihui (1615). Character dictionaries have historically been indexed using radical-and-stroke sorting, where characters are grouped by radical and sorted within each group by stroke number. Some modern dictionaries arrange character entries alphabetically according to their pinyin spelling, while also providing a traditional radical-based index.
  
  Before the invention of romanisation systems for Chinese, the pronunciation of characters was transmitted via rime dictionaries. These used the fanqie (反切; ' reverse cut ') method, where each entry lists a common character with the same initial sound as the character in question, alongside one with the same final sound.