Fast v. i. [imp. & p. p. Fasted; p. pr. & vb. n. Fasting.]
  1. To abstain from food; to omit to take nourishment in whole or in part; to go hungry.
     Fasting he went to sleep, and fasting waked.   --Milton.
  2. To practice abstinence as a religious exercise or duty; to abstain from food voluntarily for a time, for the mortification of the body or appetites, or as a token of grief, or humiliation and penitence.
     Thou didst fast and weep for the child.   --2 Sam. xii. 21.
  Fasting day, a fast day; a day of fasting.