Chinese equivalent of eggcorns? An eggcorn is:


  In linguistics, an eggcorn is an idiosyncratic substitution of a word or phrase for a word or words that sound similar or identical in the speaker's dialect (sometimes called oronyms). The new phrase introduces a meaning that is different from the original but plausible in the same context, such as "old-timers' disease" for "Alzheimer's disease". An eggcorn can be described as an intra-lingual phono-semantic matching, a matching in which the intended word and substitute are from the same language. 


Wikipedia also gives a bunch of English examples:


  
  ex-patriot instead of expatriate  
  mating name instead of maiden name
  on the spurt of the moment instead of on the spur of the moment
  preying mantis instead of praying mantis
  for all intensive purposes instead of for all intents and purposes
  


What similar phenomenons happens in Chinese?
白字 http://www.cantonese.sheik.co.uk/dictionary/words/14500/
wrong character of phonetic equivalent

Examples of 白字詞句 (words or phrases contain wrong character of phonetic equivalent):

'白撞'(to trespass under a false pretext) --&gt; 白狀 (狀 is a wrong character that sounds the same as 撞 in Cantonese; 白狀 literally means 'baseless account')

'脾氣' (temperament)--&gt; '皮氣' (皮 is a wrong character that sounds the same as  脾;'皮氣' literally means 'skin and Chi' implies 'outside and inside')

漫長競賽 (long long competition) --&gt; '萬場競賽' (countless competition) (萬場 and 漫長 sound similar in Cantonese)

'量少非君子, 無度不丈夫' --&gt;  '量少非君子, 無毒不丈夫' (道 was misheard as 毒)


The phrase '無度不丈夫' (true man cannot be without magnanimity) from the original idiom was misheard as  '無毒不丈夫' (true man cannot be without venom) and the wrong one got spread so far and wide, it became a common phrase on its own. Nowadays, when someone is about to do evil thing, this phrase would be used for an excuse