I've been fascinated with the strange occurrence in our language where we have words that could only exist along with a prefix or suffix. I've often though about how humorous they are in the moment, but I've never made a list and often forget that I ran into them. I should get around to making a list, and I could use your help. Here are a couple that spring to mind immediately:

nonchalant - would "chalant" be acting in an overbearingly obvious manner?

overwhelmed/underwhelmed - you can never be just "whelmed", except maybe in Europe