We don't have synonyms for copyediting yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are copy editing, copy-editing and copywriting.
(n) :
Alternative spelling of copy editing. [The correction of the spelling, grammar, formatting, etc. of printed material and preparation of it for typesetting, printing, or online publishing.]
(n) :
Alternative spelling of copy editing. [The correction of the spelling, grammar, formatting, etc. of printed material and preparation of it for typesetting, printing, or online publishing.]