McElligott is a character from the children's book "McElligot's Pool," written and illustrated by Dr. Seuss. The story follows a young boy named Marco who imagines the various fish he could catch in a seemingly small and unremarkable pool. The book emphasizes themes of imagination and creativity, showcasing how a simple setting can lead to grand adventures. Through whimsical illustrations and playful rhymes, Dr. Seuss encourages readers to dream big and explore the possibilities that lie within their own surroundings.