Entry 1 sense Webster, 1913 Caliginous /kə-lĭjʹə-nəs/ · Ca·lig·i·nous · IPA /kəˈlɪd͡ʒənəs/ 01 a. Affected with darkness or dimness; dark; obscure. 1. Affected with darkness or dimness; dark; obscure.[R.] “The caliginous regions of the air.” — Hallywell.