Quick thinking is a term used to describe the ability to think and respond quickly in a given situation. The crossword solutions for this term are WIT (3 letters), SMART (5 letters), AGILE (5 letters), SHARP (5 letters), and ASTUTE (6 letters). WIT refers to the ability to think and respond quickly with humor or intelligence. SMART implies having a high level of intelligence and the ability to think critically. AGILE suggests being able to move quickly and easily, as well as think quickly. SHARP implies having a keen intellect and the ability to think quickly and accurately. ASTUTE implies having a SHARP mind and the ability to think quickly and shrewdly.