from
The Collaborative International Dictionary of English v.0.48
Bowlder \Bowl"der\, Boulder \Boul"der\, n. [Cf. Sw. bullra to
roar, rattle, Dan. buldre, dial. Sw. bullersteen larger kind
of pebbles; perh. akin to E. bellow.]
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1. A large stone, worn smooth or rounded by the action of
water; a large pebble.
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2. (Geol.) A mass of any rock, whether rounded or not, that
has been transported by natural agencies from its native
bed. See {Drift}.
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{Bowlder clay}, the unstratified clay deposit of the Glacial
or Drift epoch, often containing large numbers of
bowlders.
{Bowlder wall}, a wall constructed of large stones or
bowlders.
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