A means of referencing items with respect to time and ancestry such that an item without antecedents is designated as the first or n-th generation, and subsequent derivations are designated as n 1, n 2, etc.是什么意思_A means of referencing items with respect to time and ancestry such that an item without antecedents is designated as the first or n-th generation, and subsequent derivations are designated as n 1, n 2, etc.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句