Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
spĕcŭlātōrĭus, a, um, adj. [speculator], of or belonging to spies or scouts: navigia, spy-boats, vessels of observation, Caes. B. G. 4, 26; also called speculatoriae naves, Liv. 30, 10, 14; 35, 26, 9; 36, 42, 8; and caliga, worn by spies or scouts, Suet. Calig. 52.
Hence, subst.: spĕcŭlātōrĭa, ae, f.