Hyphens, En Dashes, Em Dashes

Q. Is co-worker hyphenated? The dictionary that I have does not list coworker—it only lists the word in relation to the prefix co- and shows co-worker in a list with other words. I looked in the hyphenation section of the manual that shows examples, and I don’t see examples for a prefix (like co-) and a noun.

A. Please see the examples in (can you guess?) the CMOS hyphenation table at 7.85, section 4, under co: “coequal, coauthor, coeditor, coordinate, cooperation, coworker, but co-op, co-opt.”