In Greek mythology, a naiad is a type of female spirit or nymph associated with fresh water, such as rivers, streams, and fountains. The ancient Greeks believed that each river had its own naiad who protected the waters and the creatures within.
A naiad is the aquatic larval stage of certain insects, such as dragonflies and mayflies, which live in water before maturing into adults. The pond was teeming with naiads, which would soon transform into graceful dragonflies.
Any of several slender, submerged aquatic plants of the genus Najas, commonly called water nymphs. Aquarists often cultivate naiads to oxygenate their tanks.