The hackle is a clipped feather plume that is attached to a military headdress.
In the British Army and the armies of some Commonwealth countries the hackle is worn by some infantry regiments, especially those designated as fusilier regiments and those with Scottish and Northern Irish origins. The colour of the hackle varies from regiment to regiment.
The hackle should not be confused with the much longer set of feathers commonly attached to the feather bonnet worn by Highland regiments (now usually only worn by drummers, pipers and bandsmen).
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