The crossword solutions for the term NOT SO COOL are NERDIER (7 letters), TENSER (6 letters), and LAMER (5 letters). NERDIER is an informal term used to describe someone who is overly intellectual or socially awkward. TENSER is an adjective meaning more anxious or nervous. Lastly, LAMER is an informal term used to describe someone who is not cool or fashionable. All three terms are used to describe someone who is not so cool.