Unthoughtfulness is a character flaw that many people struggle with, but finding the perfect synonym for this word can be challenging. A few synonyms for unthoughtfulness include inconsiderateness, disregard, negligence, thoughtlessness, and insensitivity. These words all reflect a lack of consideration for others and a tendency to act without thinking about the consequences of one's actions. Each of these synonyms has its own unique connotations, and some may be more suitable than others depending on the context. Whether you are trying to describe someone's behavior or trying to avoid employing the word unthoughtfulness repeatedly in your writing, these synonyms can be a valuable addition to your vocabulary.