The term 'Future Flies' is a metaphor for the idea that time passes quickly and that the future is always coming. The crossword solution for this term is 'LARVAE, ' which refers to the immature stage of an insect's life cycle. LARVAE are the first stage of development for many insects, including flies, and they eventually grow into adults. This metaphor suggests that time passes quickly and that the future is always coming, just like LARVAE grow into adults.