Chuffiest is a descriptive word that means someone or something is very pleased with themselves or their achievements. Some other synonyms for chuffiest include conceited, smug, self-satisfied, egotistical, vainglorious, arrogant, cocky, haughty, and pompous. These words describe individuals who are overly confident and have a high opinion of themselves, often to the point of being unbearable. However, one must be careful not to confuse chuffiest with confidence or self-esteem, which are healthy traits. Chuffiest is often used in a negative context and implies excessive self-importance or pride. So, it's essential to use it judiciously while choosing alternative words.