horsefeathers

Meanings

1. Indicates disbelief.

1. plural of horsefeather (singular not used)

1. Nonsense; indicates disbelief.
2. Long hair on lower legs of a draft horse (e.g., Clydesdale), especially the rear legs.
3. Feathering strips.

Etymology

The "nonsense" sense, a euphemism for horseshit, is horse + feathers, a nonexistent item as only birds have feathers. Compare hen’s teeth. The "horse hair" sense notes the similarity of that hair to bird feathers. Regarding the roofing sense, compare feathering strip and horsefeathers.