Definify.com

Webster 1913 Edition


Micraster

‖

Mi-cras′ter

,
Noun.
[NL., fr. Gr.
μικρόσ
small + [GREEK] star.]
(Paleon.)
A genus of sea urchins, similar to Spatangus, abounding in the chalk formation; – from the starlike disposal of the ambulacral furrows.