\Ca*lig"i*nous\, a. [L. caliginosus; cf. F.
caligineux.]
Affected with darkness or dimness; dark; obscure. [R.]
--Blount.
      The caliginous regions of the air.       --Hallywell.
-- {Ca*lig"i*nous*ly}, adv. -- {Ca*lig"i*nous*ness}, n.