What is an arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its center. Diadem lemur. (Zoöl.) See Indri. -- Diadem spider (Zoöl.), the garden spider called?

diadem — (Her.) An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its center. Diadem lemur. (Zoöl.) See Indri. -- Diadem spider (Zoöl.), the garden spider. (Webster's 1913.)

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