hoodoo
HOO-doo
A tall, thin, often fantastically shaped tower of rock left standing by differential erosion — a column of softer material capped by a harder stone that has protected the rock beneath it while everything around eroded away. Hoodoos look improbable, as if they might topple at any moment, and they do — just slowly. Bryce Canyon is the most famous hoodoo landscape on earth.
Etymology
Possibly from voodoo, or from West African hudu. The formations look like they were conjured rather than carved.
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