Emergence: “In the stages of the life cycle of a dragonfly, once the egg is laid upon a floating plant or dropped into the water, it gestates, hatches and may remain for up to four years in this larval form called a nymph. 

This is a precursor to the dragonfly. (Dragonflies skip the cocoon stage, moving from egg directly to nymph.) At some point, the nymph climbs onto a rock or leaf and there emerges from its former body and takes on the shape and character of the adult dragonfly.