nymph , in Greek mythology, female divinity associated with various natural objects. It is uncertain whether they were immortal or merely long-lived. There was an infinite variety of nymphs. Some represented various localities, e.g., acheloids, or nymphs of the River Achelous; others were identified with the part of nature in which they dwelled, e.g., oreads, or mountain nymphs; and still others were associated with a particular function of nature, e.g., hamadryads, or tree nymphs, whose lives began and ended with that of a particular tree. Nymphs were represented as young, beautiful, musical, amorous, and gentle, although some were associated with the wilder aspects of nature and were akin to satyrs; others were vengeful and capable of destruction, as in the story of Daphne . Other important nymphs were naiads, nymphs of streams, rivers, and lakes; nereids, daughters of Nereus, who lived in the depths of the Mediterranean Sea; dryads, tree nymphs; and oceanids, 3,000 ocean nymphs who were the daughters of Oceanus. Arethusa , Thetis , Calypso , and Echo were famous nymphs. The nymphs' cult was widespread in Greece.