noun
development code name; project code name
Used in business and technology contexts for the internal name of a product or project before its official release.
この新製品の開発コードは「Project X」です。
The development code name for this new product is 'Project X'.
コードネーム is a more general 'code name' (e.g., for a person or operation), while 開発コード specifically refers to a product or project under development.
Compound of 開発 (development) and コード (code). A straightforward modern technical term.