opt inglossary / OPT IN opt in, vb. To choose to participate in (something) (when the choice of settling or not settling came, the Joneses opted in, hoping to avoid a lengthy trial). 词条贡献者 资深译员Barbara,毕业于国内顶尖的高级翻译学院,擅长翻译各类与兼并收购相关的法律文件。