Source : Webster's Revised Unabridged Dictionary (1913)

Caliginous \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.