Lewis & Short

anxĭĕtas, ātis, f. [anxius].

  1. I. The quality or state of anxius, anxiety (as a per manent condition, while angor, anguish, is only momentary; cf. Hab. Syn. 108, and v. angor), Cic. Tusc. 4, 12, 27: perpetua anxie tas, Juv. 13, 211.
    But sometimes = angor, temporary anguish, fear, trouble, etc.: animi, Ov. P. 1, 4, 8; Curt. 4, 13: divortii anxietate mortuus, Plin. 7, 53, 54, § 186.
  2. II. Anxious care, carefulness in regard to a thing (only post-Aug.): quaerendi, judicandi, comparandi anxietas, Quint. prooem. 8 fin.: anxietas et quasi morositas disputationis, Gell. 1, 3, 12; cf. anxius, B.