• Webster's Revised Unabridged Dictionary
    • n Arillus (Bot) 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.
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Century Dictionary and Cyclopedia
    • n arillus Same as aril.
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Chambers's Twentieth Century Dictionary
    • n Arillus a peculiar covering of the seed of some plants, formed by an expansion of the cord (funiculus) which attaches the ovule to the placenta, or of the placenta itself
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Webster's Revised Unabridged Dictionary
From LL. arilli, dry grapes, perh. fr. L. aridus, dry: cf. F,. arille,
Chambers's Twentieth Century Dictionary
Low L. arillus.


In literature:

Seeds flat and margined, covered with a white bony arillus.
"The Manual of the Botany of the Northern United States" by Asa Gray