The term LEAST CHALLENGING can be broken down into two crossword solutions: EASIEST (7 letters) and TAMEST (6 letters). EASIEST is an adjective that means requiring the least effort or difficulty, while TAMEST is an adjective that means lacking in spirit or energy. Both words are used to describe something that is not difficult or demanding. Together, they form the phrase LEAST CHALLENGING, which implies that something is not hard or strenuous.