The term 'MISCHIEVOUS PIXIE' can be broken down into two words: 'MISCHIEVOUS' and 'PIXIE'. The word 'MISCHIEVOUS' is an adjective that describes someone who is naughty or playful, often in a way that is not malicious. The word 'PIXIE' is a mythical creature, usually depicted as a small, winged humanoid with magical powers. Together, the two words form a phrase that describes a MISCHIEVOUS, magical creature. The crossword solution for this term is 'ELF', which is another mythical creature, typically depicted as a small, human-like being with pointed ears and magical powers.