'Supplementation' definitions:

Definition of 'supplementation'

(from WordNet)
noun
A quantity added (e.g. to make up for a deficiency) [syn: supplement, supplementation]
noun
The act of supplementing [syn: supplementation, subjunction, subjoining]

Definition of 'Supplementation'

From: GCIDE
  • Supplementation \Sup`ple*men*ta"tion\, n. The act of supplementing. --C. Kingsley. [1913 Webster]