The term 'MOST BLUE' can be broken down into three crossword solutions: TRUEST (6 letters), SALTIEST (8 letters), and SADDEST (7 letters). The word 'TRUEST' is an adjective meaning 'MOST faithful or loyal, ' while 'SALTIEST' is an adjective meaning 'having the MOST salt.' Lastly, 'SADDEST' is an adjective meaning 'MOST sorrowful or unhappy.' All three words are used to describe something that is the MOST extreme in its respective category.