Source : Webster's Revised Unabridged Dictionary (1913)

Shrovetide \Shrove"tide`\, n. [From shrive to take a confession
   (OE. imp. shrof, AS. scr[=a]f) + tide.]
   The days immediately preceding Ash Widnesday, especially the
   period between the evening before Quinguagesima Sunday and
   the morning of Ash Wednesday.

Source : WordNet®

Shrovetide
     n : immediately preceding Lent