The document defines vocabulary words related to puffins and their habitats. It provides the terms puffins, pufflings, burrow, hatch, underground, and cliff along with short descriptions of each word. Puffins are brightly colored seabirds, pufflings are young puffins ready to fly, a burrow is an underground animal hole, hatching is breaking out of a shell, underground means beneath the earth, and a cliff is an edge of land.