Covered with boulders; surrounded by or made of large rocks.
From 'be-' plus 'bouldered' (covered with boulders), from 'boulder,' which comes from Swedish 'bullersten.' The prefix creates an adjective describing a landscape feature.
Geological surveys and hiking guides must have used 'bebouldered' to describe rocky terrain—it's more specific than just 'rocky,' suggesting an overwhelming abundance of large stones.
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