Chicago style uses the latter even though their dictionary of choice, Merriam-Webster, does not. (Merriam-Webster spells the verb as one word though, which is how Chicago justifies its preference.) AP style gives the two-word spelling. To further complicate matters, the term is hyphenated in Britain (although they prefer “sub editor”).
Readers of this blog know I spell it as two words, maybe because I started out with APA style (American Psychological Association), which spells it this way. Given our profession’s penchant for consistency, shouldn’t we come to a consensus?
