Knuckle-headed is a term that refers to a person who is considered foolish or dense. It is always advisable to use synonyms when writing to add variety and avoid overusing the same words. Some alternative words to describe such an individual include dull, dim-witted, blockheaded, boneheaded, thick, or dense-minded. These synonyms may be used depending on the context of the sentence. An excellent use of such synonyms can make our language more precise and descriptive while making the text more appealing to readers. Therefore, it is essential to keep exploring new and diverse words to create more engaging content.