The term 'out of one's mind' is an idiom used to describe someone who is mentally unstable or irrational. This phrase can be broken down into several crossword solutions, such as 'LOCO' (4 letters), 'ASIDE' (5 letters), 'INSANE' (6 letters), 'MAD' (3 letters), 'DERANGED' (8 letters), and 'unhinged' (8 letters). All of these words are synonyms for the phrase 'out of one's mind' and can be used to describe someone who is mentally unwell.