The crossword solutions for the term LEAST DULL are KEENEST, which is a 7-letter word. The term 'keenest' is an adjective that means having or showing a quick and eager appreciation, understanding, or intelligence. It is often used to describe someone who is very enthusiastic and passionate about something. In comparison to the term 'DULL', which means lacking in interest or excitement, the term 'keenest' implies that the person or thing is the most interesting or exciting of its kind.