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anchor ice

noun
  1. ice formed below the surface of a body of water that attaches either to a submerged object or to the bottom.

Origin of anchor ice

An Americanism dating back to 1805–15
Also called bottom ice, ground ice.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for anchor ice

anchor ice

noun
  1. Canadian ice that forms at the bottom of a lake or river
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012