Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sub-lūco, āre, 1, v. a. [lux], to trim, cut away, thin out the branches of a tree, to admit light: sublucare arbores est ramos earum supputare, et veluti subtus lucem mittere, Fest. p. 348 Müll.: arbor … nisi a domino sublucari non potest, isque conveniendus est ut eam sublucet, Paul. Sent. 5, 6, 13; cf. colluco.