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ˈpowder-ˌdown
[f. powder n.1 + down n.2, rendering Ger. puder-dunen or staub-dunen (pl.), lit. powder-downs (i.e. down-plumules, ‘down’), introduced 1840 by Nitzsch (Pterylographie vii).]
Name for peculiar down-feathers or plumules, found in various birds in definite tracts or patches: so called from the bluish-white powdery or scurfy substance into which they disintegrate; by Coues called pulviplumes. (Sometimes, less correctly, applied to the powder or scurf.) Also attrib., as in powder-down feathers, powder-down patch or powder-down tract, a patch of powder-downs.
1861A. D. Bartlett in Proc. Zool. Soc. 131 This has led me to the discovery of two remarkable powder-down patches. 1867P. L. Sclater tr. Nitzsch's Pterylogr. vii. 38 The powder-down-feathers are intruded among the lateral feathers of the great saddle of the spinal tract. 1894Newton Dict. Birds 242 The ‘Downs’ are almost always concealed by the Contour-feathers, and are smaller, more fluffy, and more numerous... A peculiarly modified kind are the Powder-downs. Ibid. 738 Powder-downs are so called from the powder produced by the continuous disintegration of the numerous brush-like barbs and barbules, into which the barrel is constantly splitting as it grows without forming a principal shaft. |