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Webster 1913 Edition
Derrick
Der′rick
,Noun.
1.
A mast, spar, or tall frame, supported at the top by stays or guys, and usually pivoted at the base, with suitable tackle for hoisting heavy weights, such as stones in building.
Derrick crane
, a combination of the derrick and the crane, having facility for hoisting and also for swinging the load horizontally.