The term 'COOL CUCUMBER' can be broken down into four crossword solutions: SEA (3 letters), IMPERTURBABLE (13 letters), SIMILE (6 letters), and ASA (3 letters). SEA stands for the body of salt water that covers most of the Earth's surface, while IMPERTURBABLE means not easily disturbed or upset. SIMILE is a figure of speech in which two unlike things are compared using the words 'LIKE' or 'AS, ' and ASA is an acronym for the American Sociological Association. Together, these four words form the phrase 'COOL CUCUMBER, ' which is used to describe someone who is calm and composed in difficult situations.