ANNOTATION
annotation, annotating
(noun) the act of adding notes
note, annotation, notation
(noun) a comment or instruction (usually added); “his notes were appended at the end of the article”; “he added a short notation to the address on the envelope”
Source: WordNet® 3.1
Etymology
Noun
annotation (countable and uncountable, plural annotations)
a critical or explanatory commentary or analysis
a comment added to a text
the process of writing such comment or commentary
(computing) metadata added to a document or program
(genetics) information relating to the genetic structure of sequences of bases
Source: Wiktionary
An`no*ta"tion, n. Etym: [L. annotatio: cf. F. annotation.]
Definition: A note, added by way of comment, or explanation; -- usually in
the plural; as, annotations on ancient authors, or on a word or a
passage.
Source: Webster’s Unabridged Dictionary 1913 Edition