Definition of "codeword"

codeword

noun
plural codewords
1. (cryptography) A string representing an encoded piece of text.
2. A word or phrase (or by extension a concept) used to make a (concealed) reference to another word or concept.
  Quotations
  Even the most virtuous concepts were scrutinised by governments eager to interpret them as codewords for something unwelcome.
  1993, The Economist
  El Niño has hit the headlines as a codeword for bad weather, especially in the Pacific and California. But there is a little more to it than that.
  2007, Rough Guides, The Rough Guide to the Energy Crisis, UK: Rough Guides, page 194
  The Catholic Church has had problems in the past with fluid notions of gender, most particularly at the United Nations where some groups have used gender as a codeword for reproductive health rights which are deemed to include abortion.
  2013, Paul Vallely, Pope Francis: Untying the Knots, A&C Black, page 379
3. A type of crossword puzzle where the letters of the alphabet are represented by numbers and the solver must identify them by their position and frequency.