Definition - What does Soundex mean?
Soundex is a phonetic algorithm developed in the early 1900s by Robert C. Russell and Margaret King Odell. It was used in the U.S. census from 1890 to 1920. It enjoyed a resurgence in the 1960s and is now archived by the U.S. National Archives and Records Administration.
Techopedia explains Soundex
Soundex attempts to find similar names or homophones using phonetic notation. The program retains letters according to detailed equations, to match individual names for the purposes of large volume research.
With the advent of high-powered modern computers, and then of natural language processing later in the 20th century, technologies like Soundex became relatively primitive and largely obsolete. Modern algorithms work on a much more detailed basis than Soundex's system of phonetic markers. However, these types of technologies are preserved in the historical record to show the art of algorithm development and modern research.