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head wall

noun
  1. a cliff or steep slope rising at one end of a glaciated valley.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
headwall in Science

headwall

[hĕd′wôl′]
  1. A steep slope or precipice rising at the head of a valley or glacial cirque.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.