The term 'Mind Boggler' can be defined as something that is difficult to understand or solve. The two crossword solutions for this term are 'ENIGMA' and 'OPIATE'. ENIGMA is a six-letter word that refers to something that is mysterious or puzzling. It is derived from the Greek word 'ainigma', which means 'RIDDLE'. OPIATE is also a six-letter word that refers to a drug that is used to reduce pain or induce sleep. It is derived from the Latin word 'OPIUM', which is a narcotic drug derived from the poppy plant.