Excuseless is a term used to describe someone who is unable to provide an acceptable reason or justification for their actions or behavior. Some synonyms for excuseless include inexcusable, unjustifiable, indefensible, unforgivable, and irremediable. These terms all convey a sense of wrongdoing or error that cannot be easily explained away. Other related words that can be used in place of excuseless include culpable, blameworthy, and guilty. Ultimately, when someone is referred to as excuseless, it suggests that their actions were lacking in integrity, justification, or moral responsibility. However, it's important to note that while these terms may be harsh, they can also serve as a reminder to take ownership of our mistakes and work to do better in the future.