sothiac

CIDE DICTIONARY

sothiac, a. 

 Of or pertaining to Sothis, the Egyptian name for the Dog Star; taking its name from the Dog Star; canicular.  [1913 Webster]

Sothiac year, or Sothic year (Chronol.), the Egyptian year of 365 days and 6 hours, as distinguished from the Egyptian vague year, which contained 365 days. The Sothic period consists of 1,460 Sothic years, being equal to 1,461 vague years. One of these periods ended in July, a. d. 139.