Source : Webster's Revised Unabridged Dictionary (1913)

Sothiac \So"thi*ac\, Sothic \Soth"ic\, a.
   Of or pertaining to Sothis, the Egyptian name for the Dog
   Star; taking its name from the Dog Star; canicular.

   {Sothiac}, 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.

Sothiac \So"thi*ac\, Sothic \Soth"ic\, a.
   Of or pertaining to Sothis, the Egyptian name for the Dog
   Star; taking its name from the Dog Star; canicular.

   {Sothiac}, 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.