Synonyms for Annotate:

n.

complete, backdate, fill in, caption, fill out, enshrine, address, enter, date. annotate (noun)
gloss, footnote, comment.
comment (noun)
expound.

v.

communication (verb)
gloss, comment.
creation (verb)
footnote.
interpret (verb)
paraphrase, condense, transcribe, render, decipher, rephrase, restate, explain, report, comment, decode, translate, interpret, analyze, elucidate.

Other synonyms:

fill out, enshrine, date, caption. fill in, enter, backdate. complete. address. Other relevant words:
complete, backdate, enshrine, footnote, date, gloss, address, caption, enter, expound.