1. A stiffly starched frilled or pleated circular collar of lace, muslin, or other fine fabric, worn by men and women in the 1500s and 1600s.

2. A distinctive collarlike projection around the neck, as of feathers on a bird or of fur on a mammal.

3. A migratory sandpiper (Philomachus pugnax) of the Eastern Hemisphere, the male of which has collarlike, erectile feathers around the neck during the breeding season.