Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† hēlĭoscŏpĭon, ii, n., = ἡλιοσκόπιον, a species of heliotropium, Plin. 22, 21, 29, § 57; called also: helioscopum, App. Herb. 108.