/ Dictionary / Index A ambulacrum: Meaning and Definition of Find definitions for: am•bu•lac•rum Pronunciation: (am"byu-lak'rum, -lā'krum), [key] — pl. -lac•ra one of the radial areas in an echinoderm, as the sea urchin, bearing the tube feet by which the creature moves. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ambulacrum (Thesaurus) ambsace ambulance Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language