I'm searching for a rare word that means a small space/dwelling that is much larger on the inside than it appears from the exterior. It has been in 2 stories I know of:
- shown as a magical tent: Ali Baba and The 40 Thieves,
- and most recently in the Harry Potter movies as Weasley's tent at the Quidditch World Cup. Perkin's tent / harrypotter.wikia.com.