Nitwits is a derogatory term used to describe individuals who are perceived as foolish, stupid, or lacking in common sense. There are several synonyms available to replace the word nitwits, including dummies, idiots, imbeciles, morons, and blockheads. These words are often used to insult someone's intelligence and are considered inappropriate in most social situations. While these words may be used in jest among friends or family members, it is essential to use tact and proper judgment when choosing language. It is always better to communicate clearly and respectfully, rather than resorting to derogatory words that can be hurtful or offensive to others.