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echi·nus | \ i-ˈkī-nəs 
\
\ plural echini\ i-ˈkī-ˌnī \
\Definition of echinus
1 : sea urchin
2a : the rounded molding that lies directly beneath the abacus in the capital of a column in the Greek Doric order
b : a similar member in other orders
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Time Traveler for echinus
The first known use of echinus was in the 14th century
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