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definitions

barrow pit

noun Western U.S.
  1. a roadside borrow pit dug for drainage purposes.

Origin of barrow pit

apparently in reference to the mound of earth dug from the pit (see barrow2); variants with bar perhaps from regional pronunciation of barrow
Also called bar pit, bar ditch.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018