/'pəʊsskrɪpt; `posskrɪpt/
n ~ (to sth)
1 (abbr 缩写 PS) extra message added at the end of a letter after the signature （信末签名後的）附笔, 又及
*She mentioned in a postscript to her letter that the parcel had arrived. 她在信末附笔中说包裹已寄到.
2 facts or information added to sth after it is completed 补遗; 补笔; 後话
*There was an interesting postscript to these events when her private diaries were published. 她的日记发表後, 补充了一些有关这些事件的趣闻.

n[C]PS
[Date: 1500-1600; Language: Modern Latin;Origin: postscriptum, from Latin postscribere 'to write after']
a message written at the end of a letter after you have signed your name
extra details or information that you add after a story or account
postscript to
　There's an interesting postscript to this tale.