The term 'SMART GUY' can be represented by five different crossword solutions: BRAIN (5 letters), ALEC (4 letters), ALECK (5 letters), ACE (3 letters), WISEMAN (7 letters), and INTELLIGENTGENT (15 letters). BRAIN is a common term used to describe someone who is INTELLIGENT, while ALEC, ALECK, and ACE are all variations of the same name, which is often used as a nickname for someone who is clever. WISEMAN is another word for someone who is wise, and INTELLIGENTGENT is a combination of the words 'INTELLIGENT' and 'GENTLEMAN, ' which together suggest a person who is both SMART and well-mannered.