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noun /ˈpleɪshəʊldə(r)/
  /ˈpleɪshəʊldər/
- (specialist) a symbol or piece of text that temporarily replaces something that is missing(替代缺失部分的)占位符,占位文字 
- (linguistics语言学 位标(句子中必要但无实际意义的词项,如 It's a pity she left 中的 it)