Lewis & Short

ăcūlĕātus, a, um, adj. [aculeus], furnished with stings or prickles, thorny, prickly.

  1. I. Lit., of animals and plants: animalia, Plin. 20, 22, 91: bruchus, Vulg. Jer. 51, 27: herbae, Plin. 24, 19, 119: ictus, a puncture made by a sting, Plin. 20, 21, 84, § 223.
  2. II. Fig.
    1. A. Stinging, pointed, sharp: istaecaculeata sunt, animum fodicant, Plaut. Bacch. 1, 1, 30: litterae, Cic. Att. 14, 18, 1.
    2. B. Subtle, cunning: contorta et aculeata sophismata, Cic. Ac. 2, 24.