greenfield adjective 2noun 1forms 1 adjective2 •Of a completely new development, without the need to integrate with legacy systems, etc.The NSA provides that approximately $11 billion in new investments will be made by 2028, which includes the initial investment in a greenfield project that would be completed after 2028. — 2025 •Previously untapped; free for the taking. noun[before a noun]1 •A site, to be used for housing or commerce, whose previous use (if any) was agricultural. formsgreenfields