Pò 破 literally means ‘break’, pòyīn 破音 ‘break the pronunciation’, that is: break the usual convention in pronouncing a Chinese character, not to read it in its usual pronunciation. Pòyīnzì 破音字 then refers to a character having, in addition to its usual pronunciation, another pronunciation for a different meaning.

There are two major reasons for the emergence of pòyīnzì. First, there is the loangraph (jiǎjiè 假借) phenomenon. When referring to a morpheme that lacked a character or that had not been consistently represented by a single character, ancient wri…