Definition of pipe for English Language Learners. : 1  a long, hollow tube for carrying water, steam, gas, etc. : 2  a tube with a small bowl at one end that is used for smoking tobacco. : 3  a musical instrument that is in the shape of a tube, has holes along the top, and is played by blowing.
The Blood of Olympus (mentioned) Lupa is the immortal Roman wolf goddess who trains Roman demigods in the ways of Rome. She trains the demigods at the Wolf House, then sends them to Camp Jupiter where they can join the Twelfth Legion.
The wolf that looms largest in Norse legend is the giant Fenris-wolf, a terrible agent of destruction. Fenris was the offspring of Loki, the trickster god, and a giantess; his siblings were the dread. Midgard serpent and Hel, goddess of the underworld.