Lewis & Short

Stōĭcus, a, um, adj., = Στωϊκός, of or belonging to the Stoic philosophy or to the Stoics, Stoic: schola, Cic. Fam. 9, 22 fin.: secta, Sen. Ep. 123, 14: sententia, id. ib. 22, 7: libelli, Hor. Epod. 8, 15: turba, Mart. 7, 69, 4: dogmata, Juv. 13, 121: disciplina, Gell. 19, 1, 1: Stoicum est, it is a saying of the Stoics, Cic. Ac. 2, 26, 85: non loquor tecum Stoicā linguā, sed hac submissiore, Sen. Ep. 13, 4: est aliquid in illo Stoici dei: nec cor nec caput habet, Sen. Apoc. 8.
Subst.: Stōĭcus, i, m., a Stoic philosopher, a Stoic, Cic. Par. praef. § 2; Hor. S. 2, 3, 160; 2, 3, 300; plur., Cic. Mur. 29, 61; and in philosophical writings saepissime.

    1. 2. Stōĭca, ōrum, n. plur., the Stoic philosophy, Cic. N. D. 1, 6, 15.
      Adv.: Stōĭcē, like a Stoic, Stoically: agere austere et Stoice, Cic. Mur. 35, 74: dicere, id. Par. praef. § 3.