Smart Definition
Etymology
Pronunciation
posdata
postscript
post-
after
+
data
information
Posdata means postscript and can be thought of as post-0 (after0) + data1 (information1), literally meaning 'after-information' added to a letter.
noun
  1. postscript
    An additional message added to a letter after the signature
    Añadió una posdata al final de la carta. // He added a postscript at the end of the letter.