an abbreviation consisting of letters that form a word. For example, NATO is an acronym for the North Atlantic Treaty Organization. 首字母缩略词(如NATO是北大西洋公约组织的首字母缩略词)
used in writing when you are including words from a particular book for the second time, and want to show that they are from the same book that you mentioned before 出处同上
used in writing after a word that is not spelled or used correctly to show that you have written it that way because you are repeating what someone else said or wrote 原文如此