Relying too heavily on adverbs (especially -ly words) instead of choosing stronger verbs, sharper nouns, or better action to carry meaning.
Adverb overuse is the tendency to lean on modifiers like "quickly," "angrily," "sadly," and "very" rather than finding verbs and details that convey the same meaning on their own. It's not that adverbs are evil - they're a legitimate part of speech. The problem is when they become a crutch, papering over weak verbs and telling readers how to feel instead of showing them.
Every unnecessary adverb is a missed opportunity to write something more vivid. "She walked slowly" gives us information, but "she shuffled" gives us a picture. Training yourself to spot adverb overuse will push you toward stronger, more specific writing across every sentence you craft.
King devotes several pages to arguing against adverbs, calling them a tool of the timid writer who is afraid the reader won't understand what's happening without extra signaling.
Hemingway's spare dialogue uses almost no adverbs, trusting the tension between the characters to carry the emotional weight entirely through what they say and don't say.
Rowling uses adverbs generously, especially in dialogue tags. It works for her audience and pace, proving that "rules" about adverbs are guidelines, not laws.
Not all adverbs are bad. "She arrived early" and "He turned left" use adverbs that carry real information. Target the lazy ones, not the useful ones.
Don't trade "he walked quickly" for "he walked at a fast pace with urgency in his step." Sometimes "he ran" or "he hurried" is all you need.
Words like "very," "really," "just," "quite," and "rather" are adverbs too. They're often the sneakiest offenders because they don't end in -ly.
Open a recent piece of your writing and use your word processor's search function to find every instance of "ly." For each -ly adverb you find, try to replace the adverb-verb combination with a single, more specific verb. Keep a running list of your swaps. After ten replacements, you'll start seeing patterns in which weak verbs you default to.