失笑 [ㄕ ㄒㄧㄠˋ; shi1 xiao4]
  to laugh in spite of oneself
  to be unable to help laughing
  to break into laughter
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  失笑
  しっしょう
  noun (common) (futsuumeishi)
  noun or participle which takes the aux. verb suru
  laughing at an inappropriate time
  not being able to hold back one's laughter
  colloquialism
  scornful laughter
  snicker
  snigger
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