[1] : The Collaborative International Dictionary of English v.0.48

postfix \post"fix\, n.; pl. postfixes. pref. post- + -fix, as
   in prefix: cf. f. postfixe. gram.
   a letter, syllable, or word, added to the end of another
   word; a suffix. --parkhurst.
   1913 webster
see also:
postfixes 

[2] : The Collaborative International Dictionary of English v.0.48

postfix \postfix"\, v. t.
   to annex; specifically gram., to add or annex, as a letter,
   syllable, or word, to the end of another or principal word;
   to suffix. --parkhurst.
   1913 webster

[3] : WordNet (r) 2.0

postfix
     n : an affix that is added at the end of the word syn: suffix
see also:
suffix 

Postfix >> P Words
Postfix, definition of term: Postfix
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