#knoll__mound__hillock__hummock  a small natural hill
  supertype:  hill  a local and well-defined elevation of the land
  subtype:  anthill__formicary  a mound of earth made by ants as they dig their nest
  subtype:  kopje__koppie  (South Africa) a small hill rising up from the African veld
  subtype:  molehill  a mound of earth made by moles while burrowing

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