The term 'strong and lean' can be described by two crossword solutions: SINEWY (6 letters) and WIRY (4 letters). SINEWY is an adjective that means having strong, tough, and flexible muscles. It is often used to describe athletes or people who are physically fit. WIRY is also an adjective that means having a thin, lean, and muscular body. It is often used to describe people who have a slender build but are still strong and powerful.