Q. I see that CMOS considers a line consisting of a single word or part of a word to be an “orphan.” I understand that a line that consists of only part of one word would look strange and be undesirable, but is it really necessary to avoid one-word lines in all cases? If the word is short (one or two letters), it does look strange, but I think longer words look fine and are sometimes helpful in “stretching” text that needs to fill a full page.
A. Actually, the CMOS definition of an orphan is the first line of a paragraph that appears as the last line on a page. (Please see CMOS 2.116 or under orphan in the glossary.) Paragraph 2.116 further advises, “The last word in any paragraph must not be hyphenated unless at least four letters (in addition to any punctuation) are carried over to the final line.” So yes, longer words (or parts of words) are fine as the sole content on the last line.