noun
ruff
RUF/rʌf/
A projecting collarlike ring around the neck.
The stiff white ruff forms a gathered ring around the dress form's neck.

Etymology
Ruff is probably a shortened form of ruffle, an ornamental frill gathered into folds. The name originally applied to sleeve frills before being used for the stiff, gathered collar.
In context
ruffs that were open in the front. This modification essentially meant that the ruff would now frame a woman's entire head while still giving her room to bend her neck forward.
More examples
- The bird raises its ruff of feathers during courtship.
- The actor wears a stiff white ruff around her neck.
- The shorebird called a ruff develops an elaborate feather collar.
Forms
ruff · ruffs
ruffed adjective — Having a feathered or furry neck ring