codename

/K OW0 D EH1 N EY0 M/
noun
  1. 1

    A name used to clandestinely identify somebody or something, either for military or espionage purposes, or for commercial confidentiality.

verb
  1. 1

    To give a codename to.

Source: https://en.wiktionary.org/wiki/code%20name, https://en.wiktionary.org/wiki/codename