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noun [ C ] uk/ˈpleɪs.həʊl.dər/ us/ˈpleɪs.hoʊl.dɚ/
mathematics, computing specialized占位符
a symbol or piece of text in a mathematical expression or computer instruction that can be replaced by particular pieces of information
英汉双解词典收录81607条英汉双解翻译词条，基本涵盖了全部常用单词的读音、翻译及用法，是英语学习的有利工具。