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ambulacrum

[am-byuh-lak-ruh m, -ley-kruh m]
noun, plural am·bu·lac·ra [am-byuh-lak-ruh, -ley-kruh] /ˌæm byəˈlæk rə, -ˈleɪ krə/.
  1. one of the radial areas in an echinoderm, as the sea urchin, bearing the tube feet by which the creature moves.

Origin of ambulacrum

1830–40; < New Latin, Latin: alley, walking place, equivalent to ambulā- (stem of ambulāre to walk) + -crum noun suffix denoting means
Related formsam·bu·lac·ral, adjectivein·ter·am·bu·la·crum, noun, plural in·ter·am·bu·la·cra.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ambulacrum

ambulacrum

noun plural -ra (-rə)
  1. any of five radial bands on the ventral surface of echinoderms, such as the starfish and sea urchin, on which the tube feet are situated
Derived Formsambulacral, adjective

Word Origin for ambulacrum

C19: from Latin: avenue, from ambulāre to walk
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