Found in the following dictionaries
SOWPODS (Collins Scrabble Words)
"Caligo" Definition
noun
Dimness or obscurity of sight, dependent upon a speck on the cornea.
Source: Wiktionary
Dimness or obscurity of sight, dependent upon a speck on the cornea; also, the speck itself.
Dimness of sight; caligation. also called achlys.
Source: Century Dictionary
[capitalized] [nl.] a genus of butterflies, of the subfamily brassolinæ. c. eurylochus is the enormous owl-butterfly of south america, sometimes expanding 9 inches. c. uranus is another species with an orange bar across the wings.
Source: Century Dictionary