Wil·low n.
 1. Bot. Any tree or shrub of the genus Salix, including many species, most of which are characterized often used as an emblem of sorrow, desolation, or desertion. “A wreath of willow to show my forsaken plight.” --Sir W. Scott. Hence, a lover forsaken by, or having lost, the person beloved, is said to wear the willow.
 And I must wear the willow garland
 For him that's dead or false to me.   --Campbell.
 2. Textile Manuf. A machine in which cotton or wool is opened and cleansed by the action of long spikes projecting from a drum which revolves within a box studded with similar spikes; -- probably so called from having been originally a cylindrical cage made of willow rods, though some derive the term from winnow, as denoting the winnowing, or cleansing, action of the machine. Called also willy, twilly, twilly devil, and devil.
 Almond willow, Pussy willow, Weeping willow. Bot. See under Almond, Pussy, and Weeping.
 Willow biter Zool. the blue tit. [Prov. Eng.]
 Willow fly Zool., a greenish European stone fly (Chloroperla viridis); -- called also yellow Sally.
 Willow gall Zool., a conical, scaly gall produced on willows by the larva of a small dipterous fly (Cecidomyia strobiloides).
 Willow grouse Zool., the white ptarmigan.  See ptarmigan.
 Willow lark Zool., the sedge warbler. [Prov. Eng.]
 Willow ptarmigan Zool. (a) The European reed bunting, or black-headed bunting.  See under Reed. (b) A sparrow (Passer salicicolus) native of Asia, Africa, and Southern Europe.
 Willow tea, the prepared leaves of a species of willow largely grown in the neighborhood of Shanghai, extensively used by the poorer classes of Chinese as a substitute for tea. --McElrath.
 Willow thrush Zool., a variety of the veery, or Wilson's thrush.  See Veery.
 Willow warbler Zool., a very small European warbler (Phylloscopus trochilus); -- called also bee bird, haybird, golden wren, pettychaps, sweet William, Tom Thumb, and willow wren.


 Yel·low a. [Compar. Yellower superl. Yellowest.]
 1. Being of a bright saffronlike color; of the color of gold or brass; having the hue of that part of the rainbow, or of the solar spectrum, which is between the orange and the green.
    Her yellow hair was browded [braided] in a tress.   --Chaucer.
 A sweaty reaper from his tillage brought
 First fruits, the green ear and the yellow sheaf.   --Milton.
    The line of yellow light dies fast away.   --Keble.
 2. Cowardly; hence, dishonorable; mean; contemptible; as, he has a yellow streak. [Slang]
 3.  Sensational; -- said of some newspapers, their makers, etc.; as, yellow journal, journalism, etc. [Colloq.]
 Yellow atrophy Med., a fatal affection of the liver, in which it undergoes fatty degeneration, and becomes rapidly smaller and of a deep yellow tinge. The marked symptoms are black vomit, delirium, convulsions, coma, and jaundice.
 Yellow bark, calisaya bark.
 Yellow bass Zool., a North American fresh-water bass (Morone interrupta) native of the lower parts of the Mississippi and its tributaries. It is yellow, with several more or less broken black stripes or bars. Called also barfish.
 Yellow berry. Bot. Same as Persian berry, under Persian.
 Yellow boy, a gold coin, as a guinea. [Slang] --Arbuthnot.
 Yellow brier. Bot. See under Brier.
 Yellow bugle Bot., a European labiate plant (Ajuga Chamaepitys).
 Yellow bunting Zool., the European yellow-hammer.
 Yellow cat Zool., a yellow catfish; especially, the bashaw.
 Yellow copperas Min., a hydrous sulphate of iron; -- called also copiapite.
 Yellow copper ore, a sulphide of copper and iron; copper pyrites.  See Chalcopyrite.
 Yellow cress Bot., a yellow-flowered, cruciferous plant (Barbarea praecox), sometimes grown as a salad plant.
 Yellow dock. Bot. See the Note under Dock.
 Yellow earth, a yellowish clay, colored by iron, sometimes used as a yellow pigment.
 Yellow fever Med., a malignant, contagious, febrile disease of warm climates, attended with jaundice, producing a yellow color of the skin, and with the black vomit.  See Black vomit, in the Vocabulary.
 Yellow flag, the quarantine flag.  See under Quarantine, and 3d Flag.
 Yellow jack. (a) The yellow fever.  See under 2d Jack. (b) The quarantine flag.  See under Quarantine.
 Yellow jacket Zool., any one of several species of American social wasps of the genus Vespa, in which the color of the body is partly bright yellow. These wasps are noted for their irritability, and for their painful stings.
 Yellow lead ore Min., wulfenite.
 Yellow lemur Zool., the kinkajou.
 Yellow macauco Zool., the kinkajou.
 Yellow mackerel Zool., the jurel.
 Yellow metal. Same as Muntz metal, under Metal.
 Yellow ocher Min., an impure, earthy variety of brown iron ore, which is used as a pigment.
 Yellow oxeye Bot., a yellow-flowered plant (Chrysanthemum segetum) closely related to the oxeye daisy.
 Yellow perch Zool., the common American perch.  See Perch.
 Yellow pike Zool., the wall-eye.
 Yellow pine Bot., any of several kinds of pine; also, their yellowish and generally durable timber. Among the most common are valuable species are Pinus mitis and Pinus palustris of the Eastern and Southern States, and Pinus ponderosa and Pinus Arizonica of the Rocky Mountains and Pacific States.
 Yellow plover Zool., the golden plover.
 Yellow precipitate Med. Chem., an oxide of mercury which is thrown down as an amorphous yellow powder on adding corrosive sublimate to limewater.
 Yellow puccoon. Bot. Same as Orangeroot.
 Yellow rail Zool., a small American rail (Porzana Noveboracensis) in which the lower parts are dull yellow, darkest on the breast. The back is streaked with brownish yellow and with black, and spotted with white. Called also yellow crake.
 Yellow rattle, Yellow rocket. Bot. See under Rattle, and Rocket.
 Yellow Sally Zool., a greenish or yellowish European stone fly of the genus Chloroperla; -- so called by anglers.
 Yellow sculpin Zool., the dragonet.
 Yellow snake Zool., a West Indian boa (Chilobothrus inornatus) common in Jamaica. It becomes from eight to ten long. The body is yellowish or yellowish green, mixed with black, and anteriorly with black lines.
 Yellow spot. (a) Anat. A small yellowish spot with a central pit, the fovea centralis, in the center of the retina where vision is most accurate.  See Eye. (b) Zool. A small American butterfly (Polites Peckius) of the Skipper family. Its wings are brownish, with a large, irregular, bright yellow spot on each of the hind wings, most conspicuous beneath. Called also Peck's skipper. See Illust. under Skipper, n., 5.
 Yellow tit Zool., any one of several species of crested titmice of the genus Machlolophus, native of India. The predominating colors of the plumage are yellow and green.
 Yellow viper Zool., the fer-de-lance.
 Yellow warbler Zool., any one of several species of American warblers of the genus Dendroica in which the predominant color is yellow, especially Dendroica aestiva, which is a very abundant and familiar species; -- called also garden warbler, golden warbler, summer yellowbird, summer warbler, and yellow-poll warbler.
 Yellow wash Pharm., yellow oxide of mercury suspended in water, -- a mixture prepared by adding corrosive sublimate to limewater.
 Yellow wren Zool. (a) The European willow warbler. (b) The European wood warbler.