Botany. A sharply pointed projection on a plant, such as a thorn or a spine; especially one growing directly from the epidermis or forming an extension of it.
Zoology. The sting of an insect or other animal.
((n.) A prickle growing on the bark, as in some brambles and
roses.|--|(n.) A sting.|--|)
Origin:
Early 17th century (in an earlier sense). From classical Latin acūleus sting, spine, thorn, barb, spike, prick, pang from acus needle + -leus, suffix forming diminutives.