Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ăquĭlus, a, um, adj. [etym. uncertain; cf. Paul. ex Fest. p. 22 Müll.], dark-colored, dun, swarthy (very rare): Aquilus color est fuscus et subniger, Paul. ex Fest. l. l.: Staturā haud magnā, corpore aquilo, Plaut. Poen. 5, 2, 152: color inter aquilum candidumque, * Suet. Aug. 79; Arn. 3, p. 108.