（描写语言学）通过在已存在的词或词根后加上词缀而得到新词，例如从sing（唱歌）到singer（歌唱家），从do（做）到undo（不做）

• (descriptive linguistics) the process whereby new words are formed from existing words or bases by affixation:'singer'from'sing';'undo'from'do'