sky island
n.— «From a parched sea of desert in southeastern Arizona, Mt. Graham rises 2 miles to a crested summit above the clouds. Isolated in time and space for 11,000 years, the mountain is what biologists call a sky island, “a cradle of evolution.”» —“A Desert Mountain Versus The Stars” by Carol Ann Bassett Newsday (Long Island, New York) May 5, 1987. (source: Double-Tongued Dictionary)
Further reading
If you speak a second or third language, you may remember the first time you dreamed in that new tongue. But does this milestone mean you’re actually fluent? And a couple’s dispute over the word regret: Say you wish you’d been able...