• WordNet 3.6
    • n aculeus a sharp-pointed process especially a sting of a hymenopterous insect
    • n aculeus a stiff sharp-pointed plant process
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Webster's Revised Unabridged Dictionary
    • Aculeus (Bot) A prickle growing on the bark, as in some brambles and roses.
    • Aculeus (Zoöl) A sting.
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Century Dictionary and Cyclopedia
    • n aculeus The poison-sting of the aculeate hymenopterous insects, as bees, wasps, etc. See Aculeata.
    • n aculeus In botany, a prickle; a slender, rigid, and pointed outgrowth from the bark or epidermis, as in the rose and blackberry, in distinction from a thorn, which grows from the wood.
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Webster's Revised Unabridged Dictionary
L., dim. of acus, needle


In literature:

The pastinaca oxyrinchus with a long and strong aculeus in the tayle conceued of speciall venome and virtues.
"The Works of Sir Thomas Browne" by Thomas Browne