The ruff (Philomachus pugnax) is a medium-sized wading bird that breeds in marshes and wet meadows across northern Eurasia. This highly gregarious sandpiper is migratory and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia. It is usually considered to be the only member of its genus, and the broad-billed and sharp-tailed sandpipers are its closest relatives.

The Ruff (Philomachus pugnax) is a bird in the wader family.