The term 'too sure' can be summarized by two crossword solutions: SMUG (4 letters) and OVERCONFIDENT (13 letters). SMUG is an adjective that describes someone who is excessively pleased with themselves or their achievements. It is often used to describe someone who is arrogant or self-satisfied. OVERCONFIDENT is an adjective that describes someone who has an excessive belief in their own abilities, often leading them to take risks or make decisions without considering the consequences. Both words are used to describe someone who is overly confident in their own abilities.