Q. I am curious why CMOS hyphenates “president-elect” but leaves “vice president elect” open. Would “vice president–elect” (with an en dash) not be more consistent? And why is “president-elect” hyphenated even when the term doesn’t precede a noun?
A. Good questions. As of the 18th edition of CMOS, we now write president-elect (with a hyphen, as in Merriam-Webster) and, by extension, vice president–elect (with an en dash to bridge the open compound). See CMOS 7.96, section 3, under “elect.” In these uses, elect can be considered to be a type of combining form rather than an ordinary adjective.