am·bu·lac·rum (ăm′byə-lăkrəm, -lākrəm)
n. pl. am·bu·lac·ra (-lăkrə, -lākrə)
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radial areas on the undersurface of the starfish and similar echinoderms, from which the tube feet are protruded and withdrawn.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 the Appendix of Indo-European roots.]
(click for a larger image)ambulacrum
ventral view of a starfish arm
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Indo-European & Semitic Roots Appendices
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