The definition of a postscript is an additional note or remark tacked on at the end that provides more information or details.(noun)
When you have finished and signed a letter and then add a note on the end with a P.S., this is an example of a postscript.
See postscript in Webster's New World College Dictionary
Origin: ModL postscriptum < L, neut. pp. of postscribere < post-, after (see post-) + scribere, to write: see scribe
See postscript in American Heritage Dictionary 4
noun Abbr. PS
Origin: Medieval Latin *postscrīptum
Origin: , from neuter past participle of Latin postscrībere, to write after
Origin: : post-, post-
Origin: + scrībere, to write; see skrībh- in Indo-European roots.
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