1) The practice of creating various fly-casting lures that mimic the various stages of the life cycle of insect species favored by trout, from the time the flies hatch from eggs, shed their skin, swim to the surface, unfold their wings and fly, until they ultimately mate and fall lifeless onto the water.
2) The process through which an angler performs a similar
metamorphosis as he fishes for trout, first emerging from his sleeping bag at dawn and briefly feeding voraciously then, after embarking on a boat on the stream surface, suddenly rising unsteadily to his feet, extending his rod and casting, and finally moving into a brief but spectacular flying phase, followed by a longer aquatic or swiming phase.