WordNet (r) 3.0 (2006):

word processing
    n 1: rapid and efficient processing (storage and printing) of
         linguistic data for composition and editing

The Free On-line Dictionary of Computing (30 December 2018):

word processor
word processing

    A program used to create and print (chiefly
   textual) documents that might otherwise be prepared on a
   typewriter.  The key advantage of word processor is its
   ability to make changes easily, such as correcting spelling,
   changing margins, or adding, deleting, and relocating entire
   blocks of text.  Once created, the document can be printed
   quickly and accurately and saved for later modifications.

   Today most popular word processors, such as Microsoft Word,
   offer a much greater range of facilities than the first such
   programs.

   Compare text editor.

   (1995-04-14)