Ăc'a-leph or Ăc'a-lē'pha or Ăc'a-lē'phan, n.

n.; pl. ACALEPHS, ACALEPHÆ, and ACALEPHANS. [Gr. ἀκαλήφη, a nettle.] (Zoöl.) A radiate animal of the class Medusæ, or jelly fishes; — so called from the stinging or nettling power they possess and exercise. Sometimes called sea-nettles.