Lethe
noun /ˈliːθi/
  /ˈliːθi/
[uncountable]- (in ancient Greek stories古希腊故事 勒忒,忘川(假想的河流,死者饮此河的水即忘记尘世一生) 词源via Latin from Greek lēthē ‘forgetfulness’, from the base of lanthanesthai ‘forget’.