Here are two works that drive writers crazy: maddenly vs. maddeningly.
Maddeningly means extremely annoying or exasperating, as in The traffic in downtown Los Angeles was maddeningly slow.
Maddenly is not a word. It likely appears in manuscripts because the writer is mishearing the word, which is easy to do in this case. The situation is confounded (infuriatingly so) because madden, meaning to make or become mad, is a word.
So just take a deep breath, count to 10, and if using an adverb don’t forget to also add “ing” to madden.
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My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.