Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
nĕc-ŏpīnātus (also separately, nĕc ŏpīnātus), a, um, adj., unexpected (class.): desertae disciplinae et jam pridem relictae patrocinium nec opinatum a nobis esse susceptum, Cic. N. D. 1, 3, 6: necopinata bona perspicere, id. Off. 2, 10, 36: nec opinato adventu urbem interceptam, Liv. 26, 51: in necopinatam fraudem labi, id. 27, 33: necopinatum gaudium, id. 39, 49.
Plur. as subst.: nĕcŏpīnāta, ōrum, n., the unforeseen: cum diligenter necopinatorum naturam consideres, Cic. Tusc. 3, 22, 52.
A dverb.: locum secretum ab tumultu petit, unde ex necopinato aversum hostem invadat, unexpectedly, unawares, Cic. Tusc. 4, 27, 8.
Hence, adv.: nĕcŏpīnātō (or separately, nĕc ŏpīnātō), unexpectedly: si necopinato quid evenerit, Cic. Tusc. 3, 22, 52; cf. id. ib. 3, 24, 59: aliquem necopinato videre, id. Fin. 3, 2, 8; id. Phil. 2, 31, 77: aliud novum malum necopinato exortum, Liv. 3, 15, 4.