Lewis & Short

thĕma, ătis, n., = θέμα.

  1. I. A subject or topic treated of, a theme (post-Aug.): Scholastici exempla cum dixerunt, volunt et illa ad aliquod controversiae thema redigere, Sen. Contr. 3, 20 fin.; so id. ib. 3, 28 med.; Quint. 4, 2, 28; 4, 2, 91; 7, 2, 54; 9, 2, 85 al.
  2. II. The position of the celestial signs at one’s birth, a nativity, horoscope, Suet. Aug. 94 fin.