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Webster 1913 Edition
Arillus
Ar′il
, ‖A-ril′lus
Noun.
[From LL.
arilli
dry grapes, perh. fr. L. aridus
dry: cf. F,. arille
.] (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.
Gray.
Webster 1828 Edition
Arillus
ARIL'LUS
,Noun.