Q. What is Chicago style for elongated words: huuuuge or h-u-u-u-u-ge? Thank you.
A. Chicago doesn’t have a style for such words. But maybe you’ve noticed that some people write, for example, likeeee or cuteeee. Those texting-era spellings don’t make much sense when spoken: Which part is drawn out, the final consonant or the eeee? Within a text, however, they suggest that the writer is using the last letter as an exclamation point, tapping it repeatedly for emphasis or to show enthusiasm. Hyphens would ruin this effect (cute-e-e-e?).
You could point then to texting as a precedent and repeat the letter u (as in your first version, huuuuge). It’s cleaner on the page (or screen) than the one with all the hyphens, and the intended pronunciation is obvious. Or you could go with hugeeee—but only if your goal is to use (or to mimic) the textspeak repetition of the final letter noted above. Then the e’s at the end might seem normal (That’s hugeeee!!!).
For the use of hyphens to suggest stuttering, see CMOS 12.44.