Source : Webster's Revised Unabridged Dictionary (1913)

Hail \Hail\, interj. [See {Hail}, v. t.]
   An exclamation of respectful or reverent salutation, or,
   occasionally, of familiar greeting. ``Hail, brave friend.''
   --Shak.

   {All hail}. See in the Vocabulary.

   {Hail Mary}, a form of prayer made use of in the Roman
      Catholic Church in invocation of the Virgin. See {Ave
      Maria}.

Hail \Hail\, n.
   A wish of health; a salutation; a loud call. ``Their puissant
   hail.'' --M. Arnold.

         The angel hail bestowed.                 --Milton.

Hail \Hail\ (h[=a]l), n. [OE. hail, ha[yogh]el, AS. h[ae]gel;
   akin to D., G., Dan., & Sw. hagel; Icel. hagl; cf. Gr.
   ka`chlhx pebble.]
   Small roundish masses of ice precipitated from the clouds,
   where they are formed by the congelation of vapor. The
   separate masses or grains are called hailstones.

         Thunder mixed with hail, Hail mixed with fire, must
         rend the Egyptian sky.                   --Milton.

Hail \Hail\, v. i. [imp. & p. p. {Halled}; p. pr. & vb. n.
   {Halting}.] [OE. hailen, AS. haqalian.]
   To pour down particles of ice, or frozen vapors.

Hail \Hail\, v. t.
   To pour forcibly down, as hail. --Shak.

Hail \Hail\, a.
   Healthy. See {Hale} (the preferable spelling).

Hail \Hail\, v. t. [OE. hailen, heilen, Icel. heil hale, sound,
   used in greeting. See {Hale} sound.]
   1. To call loudly to, or after; to accost; to salute; to
      address.

   2. To name; to designate; to call.

            And such a son as all men hailed me happy. --Milton.

Hail \Hail\, v. i.
   1. To declare, by hailing, the port from which a vessel sails
      or where she is registered; hence, to sail; to come; --
      used with from; as, the steamer hails from New York.

   2. To report as one's home or the place from whence one
      comes; to come; -- with from. [Colloq.] --G. G. Halpine.

Source : WordNet®

hail
     n 1: precipitation of ice pellets when there are strong rising
          air currents
     2: enthusiastic greeting

hail
     v 1: praise vociferously; "The critics hailed the young pianist
          as a new Rubinstein" [syn: {acclaim}, {herald}]
     2: be a native of; "She hails from Kalamazoo" [syn: {come}]
     3: call for; "hail a cab"
     4: greet enthusiastically or joyfully [syn: {herald}]
     5: precipitate as small ice particles; "It hailed for an hour"