Webster's Revised Unabridged Dictionary · 1913

Sothiac

Sothiac , adjective

Of or pertaining to Sothis, the Egyptian name for the Dog Star; taking its name from the Dog Star; canicular.
Collocations (1)
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.

Also: Sothic