To write on something a date that comes after the real date

A comment, not, or thought written after the letter is finished; P.S

a person who takea a college class after he or she has already graduated

a mark printed across a stamp after it is received by the post office

occurring or continuing after death; usually related to a book that is published after the author has died.

the time in society that came after the Industrial Revolution

the editing that is done after the movie, film, or video has been taped

to do something at a time or date after it was originally planned

occurring or done after death.