John Doe
/dəʊ/noun
1- Law, chiefly US an anonymous party, typically the plaintiff, in a legal action【律】〈主美〉约翰·多伊（诉讼中匿名的当事人, 多指原告）。
1.1
- N. Amer. informal a hypothetical average man〈北美, 非正式〉普通人。
词源
mid 18th cent.: originally in legal use as a name of a fictitious plaintiff, corresponding to Richard Roe, used to represent the defendant.