A fly which floats on the surface of the water by means of hackle (feather) fibers. An angler employing this technique is said to be dry-fly fishing. Found on http://www.azgfd.gov/h_f/fishing_glossary.shtml
(from the article `fly-tying`) Most fly-tying is designed for trout and salmon fishing. There are three stages of insect life that fly-tiers attempt to imitate. Dry flies, ... Found on http://www.britannica.com/eb/a-z/d/77
any fly fished upon the surface of the water; usually constructed of non-water-absorbent materials; most commonly used to imitate the adult stage of aquatic insects. Found on http://www.orvis.co.uk/intro.aspx?subject=134
A fly constructed of water resistant, lightweight and buoyant materials so as to imitate a insect that alights or floats on the surface of the water. Found on https://www.encyclo.co.uk/local/22491
any fly fished upon the surface of the water; usually constructed of non-water-absorbent materials; most commonly used to imitate the adult stage of aquatic insects. Found on https://www.encyclo.co.uk/local/22502