Definition of barbule in English:

barbule

noun

  • A minute filament projecting from the barb of a feather.

    • ‘Accordingly, even though birds without uropygial glands preened at the same rate as birds with glands, the former may have suffered more breakage of feather barbules.’
    • ‘The barbs, in turn, may bear barbules which may hook on to the barbules of an adjoining barb.’
    • ‘A few species of hummingbirds and European Starling are known to produce UV hues with coherently scattering melanin arrays in feather barbules.’
    • ‘Plumage of glandless birds was in significantly poorer condition, with more missing barbules, than the plumage of control birds with glands.’
    • ‘Well known examples include the structural colors produced by brilliant iridescent butterfly wing scales and avian feather barbules, such as the peacocks tail.’
    • ‘Bird feathers illustrate optimum design, with their interlocking barbs and barbules resulting in a strong yet extremely light structure.’
    • ‘In contrast, a flight feather has narrow barbules which do not cover the barbs.’
    • ‘Modern feathers evolved through the stages involving elongated scales that became broken up into barbs and barbules.’
    • ‘The interlocking hooks and barbules allow the feather to be ‘reset’ by the bird's preening action.’
    • ‘Well defined, functional barbules are absent.’
    • ‘Downy barbs that were initially sampled from the base of these feathers had microscopic characters that consisted of very long barbules.’
    • ‘I think they would have barbules without projections.’
    • ‘The strongly iridescent colors of bird feathers are produced by arrays of melanin granules in the barbules of feathers.’
    • ‘The barbules are the tiny feather tip structures that come off of barbs on either side of the central stem of peacock feathers.’
    • ‘It has been my impression that the mechanism whereby the barb ridges separate from one another and sculpt out the barbules, probably involves many sequential changes.’
    • ‘Increased plumage abrasion caused by a higher rate of preening could break feather barbules, leading to a reduction in plumage condition.’
    • ‘But scales are folds in skin; feathers are complex structures with a barb, barbules and hooks.’
    • ‘The vanes have parallel barbs, which suggests the presence of barbules.’
    • ‘Feathers, however bizarre or morphologically complex, consist essentially of a rachis, barbs, and barbules.’

Origin

Mid 19th century: from Latin barbula, diminutive of barba beard.

Pronunciation:

barbule

/ˈbɑːbjuːl/