What is "rainbow trout"

Rainbow \Rain"bow`\ (r[=a]n"b[=o]`), n. [AS. regenboga, akin to G. regenbogen. See Rain, and Bow anything bent.] A bow or arch exhibiting, in concentric bands, the several colors of the spectrum, and formed in the part of the hemisphere opposite to the sun by the refraction and reflection of the sun's rays in drops of falling rain.

Note: Besides the ordinary bow, called also primary rainbow, which is formed by two refractions and one reflection, there is also another often seen exterior to it, called the secondary rainbow, concentric with the first, and separated from it by a small interval. It is formed by two refractions and two reflections, is much fainter than the primary bow, and has its colors arranged in the reverse order from those of the latter.

Lunar rainbow, a fainter arch or rainbow, formed by the moon.

Marine rainbow, Sea bow, a similar bow seen in the spray of waves at sea.

Rainbow trout (Zo["o]l.), a bright-colored trout ( Salmo irideus), native of the mountains of California, but now extensively introduced into the Eastern States, Japan, and other countries; -- called also brook trout, mountain trout, and golden trout.

Rainbow wrasse. (Zo["o]l.) See under Wrasse.

Supernumerary rainbow, a smaller bow, usually of red and green colors only, sometimes seen within the primary or without the secondary rainbow, and in contact with them.

n. 1 (cx usually countable English) A trout of the species ''Oncorhynchus mykiss'', that has black spots and a pink streak running along the body. 2 (cx usually uncountable English) The fish as food.

1. n. flesh of pacific trout that migrate from salt to fresh water

2. found in Pacific coastal waters and streams from lower California to Alaska [syn: Salmo gairdneri]

The rainbow trout (Oncorhynchus mykiss) is a trout and species of salmonid native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coastal rainbow trout or Columbia River redband trout that usually returns to fresh water to spawn after living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are also called steelhead.

Adult freshwater stream rainbow trout average between , while lake-dwelling and anadromous forms may reach . Coloration varies widely based on subspecies, forms and habitat. Adult fish are distinguished by a broad reddish stripe along the lateral line, from gills to the tail, which is most vivid in breeding males.

Wild-caught and hatchery-reared forms of this species have been transplanted and introduced for food or sport in at least 45 countries and every continent except Antarctica. Introductions to locations outside their native range in the United States (U.S.), Southern Europe, Australia, New Zealand and South America have damaged native fish species. Introduced populations may affect native species by preying on them, out-competing them, transmitting contagious diseases (such as whirling disease), or hybridizing with closely related species and subspecies, thus reducing genetic purity. Other introductions into waters previously devoid of any fish species or with severely depleted stocks of native fish have created world-class sport fisheries such as the Great Lakes and Wyoming's Firehole River.

Some local populations of specific subspecies, or in the case of steelhead, distinct population segments, are listed as either threatened or endangered under the Endangered Species Act. The steelhead is the official state fish of Washington.