[am-byuh-lak-ruh
m, -ley-kruhm] 
[-lak-ruh, -ley-kruh] . | one of the radial areas in an echinoderm, as the sea urchin, bearing the tube feet by which the creature moves. |
| am·bu·lac·rum (ām'byə-lāk'rəm, -lā'krəm) n. pl. am·bu·lac·ra (-lāk'rə, -lā'krə) One of the five radial areas on the undersurface of the starfish and similar echinoderms, from which the tube feet are protruded and withdrawn. [Latin ambulācrum, walk planted with trees, from ambulāre, to walk; see ambhi in Indo-European roots.] am'bu·lac'ral adj. |