SUPPLEMENTARY
supplementary, supplemental
(adjective) added to complete or make up a deficiency; “produced supplementary volumes”
auxiliary, subsidiary, supplemental, supplementary
(adjective) functioning in a supporting capacity; “the main library and its auxiliary branches”
Source: WordNet® 3.1
Etymology
Adjective
supplementary (comparative more supplementary, superlative most supplementary)
Additional; added to supply what is wanted.
Noun
supplementary (plural supplementaries)
Something additional; an extra.
Source: Wiktionary
Sup`ple*men"tal, Sup`ple*men"ta*ry, a. Etym: [Cf. F. supplémentaire.]
Definition: Added to supply what is wanted; additional; being, or serving
as, a supplement; as, a supplemental law; a supplementary sheet or
volume. Supplemental air (Physiol.), the air which in addition to the
residual air remains in the lungs after ordinary expiration, but
which, unlike the residual air, can be expelled; reserve air.
– Supplemental bill (Equity), a bill filed in aid of an original
bill to supply some deffect in the latter, or to set forth new facts
which can not be done by amendment. Burrill. Daniel.
– Supplementary chords (Math.), in an ellipse or hyperbola, any two
chords drawn through the extremities of a diameter, and intersecting
on the curve.
Source: Webster’s Unabridged Dictionary 1913 Edition