Prudishly is how you do something when you are being prudish: in a way that shows you are easily shocked by sex or by “rude” talk, and that you rather want others to see that shock. She prudishly changed the subject. He smiled prudishly and closed the book. The word judges the manner, not just the person. It is not a common word in everyday chat; you will meet it more in stories and reviews. Same warning as the rest of this little family: it is about sexual tightness, said with disapproval, and it has nothing to do with driving carefully or saving money. For that idea you want prudently — a different adverb from a different root.

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