The term 'not extreme' can be described by the crossword solutions of 'MODERATE' (8 letters), 'CENTRAL' (7 letters), 'TEMPERATE' (9 letters), 'MEDIUM' (6 letters), 'MODEST' (6 letters), and 'middleoftheroad' (15 letters). These words all refer to a lack of extremity, meaning that something is not too far in either direction. MODERATE implies a balance between two extremes, CENTRAL suggests a position in the middle, TEMPERATE implies a mildness, MEDIUM implies an average, MODEST implies a humility, and middleoftheroad implies a lack of commitment to either side. All of these words together suggest a lack of extremity and a preference for a more balanced approach.