Witless means lacking intelligence, good judgment, or common sense. Someone described as witless makes foolish decisions or fails to understand obvious things. If a character in a story walks right into a clearly visible trap, you might call them witless.

The word comes from “wit,” which originally meant intelligence and mental sharpness, not just humor. A witless person lacks that sharpness: they miss important details, don't think through consequences, or fail to grasp what's happening around them.

You might read about a witless plan that was doomed from the start, or a witless mistake that could have been easily avoided with a moment's thought. The word carries a harsh edge: calling someone witless is a serious criticism, not gentle teasing. It suggests they're not just making one bad choice but showing a real lack of good judgment.

Sometimes people say they were scared witless, meaning so frightened that fear drove all rational thought from their minds. In this phrase, the word describes being temporarily unable to think clearly, rather than permanently lacking intelligence.