Source : Webster's Revised Unabridged Dictionary (1913)

Neologism \Ne*ol"o*gism\, n. [Cf. F. n['e]ologisme.]
   1. The introduction of new words, or the use of old words in
      a new sense. --Mrs. Browning.

   2. A new word, phrase, or expression.

   3. A new doctrine; specifically, rationalism.

Source : WordNet®

neologism
     n 1: a newly invented word or phrase [syn: {neology}, {coinage}]
     2: the act of inventing a word or phrase [syn: {neology}, {coinage}]