Definition of "decoration"

decoration

/ˌdɛkəˈɹeɪʃən/

noun
countable and uncountable, plural decorations
1. The act of adorning, embellishing, or honoring; ornamentation.
2. Any item that adorns, enriches, or beautifies; something added by way of embellishment or ornamentation.
  Quotations
  There were many wooden chairs for the bulk of his visitors, and two wicker armchairs with red cloth cushions for superior people. From the packing-cases had emerged some Indian clubs, […], and all these articles […] made a scattered and untidy decoration that Mrs. Clough assiduously dusted and greatly cherished.
  1918, W[illiam] B[abington] Maxwell, chapter XII, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company
  At the very moment he cried out, David realised that what he had run into was only the Christmas tree. Disgusted with himself at such cowardice, he spat a needle from his mouth, stepped back from the tree and listened. There were no sounds of any movement upstairs: no shouts, no sleepy grumbles, only a gentle tinkle from the decorations as the tree had recovered from the collision.
  1994, Stephen Fry, chapter 2, in The Hippopotamus
3. Specifically, any mark of honor to be worn upon the person, as a medal, cross, or ribbon of an order of knighthood, bestowed for services in war, great achievements in literature, art, etc.
4. (biochemistry, immunology) The use of exotic sugars as decoys to distract the immune system of a host
5. (Hong Kong) refurbishment; renovation