A "supplemental form" refers to an additional document or form that provides extra or supplementary information to support or complete something. It is used to add detail, clarify, or enhance the original form or document. Full definition
They are widely found in natural food sources but may be prescribed in supplemental form for a temporary time period to ensure the good bugs are happy. (hbdnutrition.com)
There are other supplemental forms of coverage, such as collision insurance, available to you. (carinsurancequote.net)
Personally, I try to eat fatty fish at least once or twice a week and I take supplemental forms of Omega - 3 from quality sources, especially when pregnant or nursing. (wellnessmama.com)