desert island

noun3

1. •
   A deserted island, an uninhabited island, especially one in the tropics and (now frequently misunderstood as) a small and almost entirely sandy desert.

   • What would I take with me to a desert island?
2. •
   [before a noun] (figurative) Describing a thing considered so personally indispensable or beloved that one could never tire of it, used especially for books and music.

   • No, no, no. It's a thought experiment. Your desert island books are the one or five or ten books that you could always learn from and never get sick of.
3. •
   An island that is completely or mostly a desert, an arid island.

   • Why are you marooning me on a desert island? It's probably full of guano. Can't I go somewhere nice?