A monadnock /məˈnædnɒk/ or inselberg is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain.
In southern and southern-central Africa, a similar formation of granite is known as a kopje, a Dutch word ("little head") from which the Afrikaans word koppie was derived.
If the monadnock is dome-shaped and formed from granite-gneiss, it can also be called a bornhardt.
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