A software and/or hardware product that is commercially ready-made and available for sale, lease, or license to the general public.
(NSA/CSS Policy 3-14)
Software and hardware that already exists and is available from commercial sources. It is also referred to as off-the-shelf.
NISTIR 7622 under Commercial off-the-shelf
(NIST SP 800-64 Rev. 2)
Hardware and software IT products that are ready-made and available for purchase by the general public.
NISTIR 7711 under Commercial-Off-The-Shelf