- added or supplementary
WordReference Random House Unabridged Dictionary of American English © 2026
ad•di•tion•al
(ə dish′ə nl),USA pronunciation adj.
ad•di′tion•al•ly, adv.
- added;
more;
supplementary:additional information.
- addition + -al1 1630–40
Collins Concise English Dictionary © HarperCollins Publishers::
additional /əˈdɪʃənəl/ adj
'additional' also found in these entries (note: many are not synonyms or translations):
accessory
- Additional Member System
- adjective
- afterburner
- afterburning
- amplification
- amplifier
- appendix
- banyan
- bells and whistles
- bezique
- bypass engine
- cambium
- capture
- chicane
- codicil
- cognomen
- corps
- crystal system
- double
- drop leaf
- duplicate
- epiphenomenon
- extension
- extra
- extra time
- extraordinary
- facing
- farther
- feathering
- fresh
- fringe benefit
- further
- hors d'oeuvre
- incentive
- insole
- intermixture
- jump seat
- leap year
- margin
- minor
- mix
- more
- new
- nickname
- odd
- other
- overprint
- overtone
- additory