razorbill

The term refers specifically to the Alca torda, a seabird often mistaken for the Atlantic puffin due to its similar size and habitat. The primary distinction lies in the bill; while the puffin possesses a brightly colored, triangular beak, the razorbill has a heavier, blunter, and entirely black bill.

In a biological context, the name evokes the sharp, cutting edge of a razor, though the bill is functionally used for diving and catching fish rather than slicing. It is typically discussed within the context of ornithology, marine biology, or coastal wildlife observation.