postscript
n.
1550s, from Latin post scriptum "written after," from neuter past participle of Latin postscribere "write after," from post "after" (see post-) + scribere "to write" (see script, n.).
〔李〕[post-=after 后；script=to write 写⇒“sth. written after 写在…后面的话”→] n. an addition to a letter，written after the name has been signed（信末签名后的）附言；又及
〔李〕[post-=after在……之后；script =to write写→“that which is written after写在后面的东西”→] n. the part written in a letter after the signature信后的附言