Word Study
arillus
CIDE DICTIONARY
arillus, n. [From LL. arilli dry grapes, perh. fr. L. aridus dry: cf. F,. arille.].
A exterior covering, forming a false coat or appendage to a seed, as the loose, transparent bag inclosing the seed of the white water lily. The mace of the nutmeg is also an aril. Gray. [1913 Webster]
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