supplemental

comparative more supplemental · superlative most supplemental

1. Acting to supplement.

   The supplementary bibliography (in Vol. VI) attests to the comprehensiveness of the effort.

   1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, Chicago, Ill.: Field Museum of Natural History, →ISBN, page viii

2. Appending.
3. Lacking a regular schedule (as in a supplemental airline).

plural supplementals

1. Something that supplements or adds to.
2. A requisition or article of legislation that provides additional funding for a program.