The term 54 ELEMENT is composed of four crossword solutions: XENON (5 letters), LIV (3 letters), ARE (3 letters), and CAR (3 letters). XENON is a chemical element with atomic number 54, which is a noble gas found in the Earth's atmosphere. LIV is an abbreviation for the Latin phrase 'Livor Mortis, ' which refers to the discoloration of the skin after death. ARE is a unit of area measurement equal to 100 square meters. Finally, CAR is an abbreviation for the word 'CARRIAGE, ' which is a vehicle used for transportation.