The Collaborative International Dictionary of English v.0.48:

Feast \Feast\ (f[=e]st), n. [OE. feste festival, holiday, feast,
   OF. feste festival, F. f[^e]te, fr. L. festum, pl. festa, fr.
   festus joyful, festal; of uncertain origin. Cf. Fair, n.,
   Festal, F[^e]te.]
   1. A festival; a holiday; a solemn, or more commonly, a
      joyous, anniversary.
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            The seventh day shall be a feast to the Lord. --Ex.
                                                  xiii. 6.
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            Now his parents went to Jerusalem every year at the
            feast of the passover.                --Luke ii. 41.
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   Note: An Ecclesiastical feast is called a immovable feast
         when it always occurs on the same day of the year;
         otherwise it is called a movable feast. Easter is a
         notable movable feast.
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   2. A festive or joyous meal; a grand, ceremonious, or
      sumptuous entertainment, of which many guests partake; a
      banquet characterized by tempting variety and abundance of
      food.
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            Enough is as good as a feast.         --Old Proverb.
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            Belshazzar the King made a great feast to a thousand
            of his lords.                         --Dan. v. 1.
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   3. That which is partaken of, or shared in, with delight;
      something highly agreeable; entertainment.
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            The feast of reason, and the flow of soul. --Pope.
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   Feast day, a holiday; a day set as a solemn commemorative
      festival.

   Syn: Entertainment; regale; banquet; treat; carousal;
        festivity; festival.

   Usage: Feast, Banquet, Festival, Carousal. A feast
          sets before us viands superior in quantity, variety,
          and abundance; a banquet is a luxurious feast; a
          festival is the joyful celebration by good cheer of
          some agreeable event. Carousal is unrestrained
          indulgence in frolic and drink.
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The Collaborative International Dictionary of English v.0.48:

Feast \Feast\, v. i. [imp. & p. p. Feasted; p. pr. & vb. n.
   Feasting.] [OE. festen, cf. OF. fester to rest from work,
   F. f[^e]ter to celebrate a holiday. See Feast, n.]
   1. To eat sumptuously; to dine or sup on rich provisions,
      particularly in large companies, and on public festivals.
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            And his sons went and feasted in their houses.
                                                  --Job. i. 4.
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   2. To be highly gratified or delighted.
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            With my love's picture then my eye doth feast.
                                                  --Shak.
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The Collaborative International Dictionary of English v.0.48:

Feast \Feast\, v. t.
   1. To entertain with sumptuous provisions; to treat at the
      table bountifully; as, he was feasted by the king.
      --Hayward.
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   2. To delight; to gratify; as, to feast the soul.
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            Feast your ears with the music a while. --Shak.
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WordNet (r) 3.0 (2006):

feast
    n 1: a ceremonial dinner party for many people [syn: banquet,
         feast]
    2: something experienced with great delight; "a feast for the
       eyes"
    3: a meal that is well prepared and greatly enjoyed; "a banquet
       for the graduating seniors"; "the Thanksgiving feast"; "they
       put out quite a spread" [syn: banquet, feast, spread]
    4: an elaborate party (often outdoors) [syn: fete, feast,
       fiesta]
    v 1: partake in a feast or banquet [syn: feast, banquet,
         junket]
    2: provide a feast or banquet for [syn: feast, banquet,
       junket]
    3: gratify; "feed one's eyes on a gorgeous view" [syn: feed,
       feast]

The Devil's Dictionary (1881-1906):

FEAST, n.  A festival.  A religious celebration usually signalized by
gluttony and drunkenness, frequently in honor of some holy person
distinguished for abstemiousness.  In the Roman Catholic Church
feasts are "movable" and "immovable," but the celebrants are uniformly
immovable until they are full.  In their earliest development these
entertainments took the form of feasts for the dead; such were held by
the Greeks, under the name _Nemeseia_, by the Aztecs and Peruvians,
as in modern times they are popular with the Chinese; though it is
believed that the ancient dead, like the modern, were light eaters.
Among the many feasts of the Romans was the _Novemdiale_, which was
held, according to Livy, whenever stones fell from heaven.