Lewis & Short

in-spērātus, a, um, adj., unhoped for, unexpected (class.).
Of inanim. and abstr. things: insperata accidunt magis saepe, quam quae speres, Plaut. Most. 1, 3, 40: insperatum et repentinum praesidium, Cic. Phil. 10, 11, 24: repentinaeque pecuniae, id. Cat. 2, 9, 20.
Of persons, Plaut. Men. 5, 9, 72; cf. in sup.: insperatissime mihi, id. Poen. 5, 3, 8.
Of unpleasant things: unlooked for, unforeseen: insperatum et necopinatum malum, Cic. Tusc. 3, 13, 28: nihil tam necopinatum, nec tam insperatum accidere potuit, Liv. 3, 26, 5.
Neutr. adv.: ex insperato, unexpectedly, Liv. 1, 25, 9; 2, 35, 1; 30, 10 fin.; Plin. 25, 2, 6, § 17 al.
Adv. in two forms.

    1. 1. inspērātē, unexpectedly, Cassiod. Var. 7, 6.
      Comp.: insperatius, Val. Max. 3, 8, ext. 2; Vulg. Sap. 11, 8.
    2. 2. inspērātō, unexpectedly (anteand post-class.): illam augeam, Plaut. Stich. 2, 1, 32 Fleck.: abiit, Lucil. ap. Non. 35, 10: aulam invenit, Plaut. Aul. Argum. 1, 14: insperato et contra opinionem, App. M. 9, p. 235, 16.