Guillemot is a collective term for three species of seabirds, the AUK (3 letters), Murre (5 letters) and Seacoot (7 letters). These birds are found in the Northern Hemisphere and are known for their ability to dive underwater to catch fish. They have black and white plumage and long, pointed wings. The Guillemot is an important part of the marine ecosystem, as it helps to keep the population of fish in balance.