Lewis & Short

Clĕanthes, is (acc. -en, Cic. N. D. 3, 2, 5; Sen. Ep. 113, 18;

  1. I. -em, Cic. Tusc. 2, 25, 60; id. Sen. 7, 23; voc. Cleanthe, id. Tusc. 3, 32, 77; Val. Max. 8, 7, ext. 11), m., = Κλεάνθης, a Stoic philosopher of Assos, pupil of Zeno and teacher of Chrysippus, Cic. Ac. 2, 23, 73; 2, 41, 126; id. Fat. 7, 14; id. Div. 1, 3, 6; id. Fin. 2, 21, 69; 4, 3, 7; Sen. Ep. 44, 3; 108, 10; id. Ben. 5, 14, 1; Val. Max. 8, 7, ext. 11.
    Plur.: archetypos servare Cleanthas, statues of Cleanthes, Juv. 2, 7.
    Hence,
  2. II. Cleanthēus, a, um, adj., of or pertaining to Cleanthes, = Stoic: fruge, i. e. praeceptis, Pers. 5, 64: turba, i. e. discipuli, Claud. Mall. Theod. 88.