Source : Webster's Revised Unabridged Dictionary (1913)

Host \Host\, n. (Biol.)
   Any animal or plant affording lodgment or subsistence to a
   parasitic or commensal organism. Thus a tree is a host of an
   air plant growing upon it.

Host \Host\ (h[=o]st), n. [LL. hostia sacrifice, victim, from
   hostire to strike.] (R. C. Ch.)
   The consecrated wafer, believed to be the body of Christ,
   which in the Mass is offered as a sacrifice; also, the bread
   before consecration.

   Note: In the Latin Vulgate the word was applied to the Savior
         as being an offering for the sins of men.

Host \Host\, n. [OE. host, ost, OF. host, ost, fr. L. hostis
   enemy, LL., army. See {Guest}, and cf. {Host} a landlord.]
   1. An army; a number of men gathered for war.

            A host so great as covered all the field. --Dryden.

   2. Any great number or multitude; a throng.

            And suddenly there was with the angel a multitude of
            the heavenly host praising God.       --Luke ii. 13.

            All at once I saw a crowd, A host, of golden
            daffodils.                            --Wordsworth.

Host \Host\, n. [OE. host, ost, OF. hoste, oste, F. h[^o]te,
   from L. hospes a stranger who is treated as a guest, he who
   treats another as his guest, a hostl prob. fr. hostis
   stranger, enemy (akin to E. guest a visitor) + potis able;
   akin to Skr. pati master, lord. See {Host} an army,
   {Possible}, and cf. {Hospitable}, {Hotel}.]
   One who receives or entertains another, whether gratuitously
   or for compensation; one from whom another receives food,
   lodging, or entertainment; a landlord. --Chaucer. ``Fair host
   and Earl.'' --Tennyson.

         Time is like a fashionable host, That slightly shakes
         his parting guest by the hand.           --Shak.

Host \Host\, v. t.
   To give entertainment to. [Obs.] --Spenser.

Host \Host\, v. i.
   To lodge at an inn; to take up entertainment. [Obs.] ``Where
   you shall host.'' --Shak.

Source : WordNet®

host
     n 1: a person who invites guests to a social event (such as a
          party in his or her own home) and who is responsible for
          them while they are there
     2: a vast multitude [syn: {horde}, {legion}]
     3: an animal or plant that nourishes and supports a parasite;
        the host does not benefit and is often harmed by the
        association [ant: {parasite}]
     4: a person who acts as host at formal occasions (makes an
        introductory speech and introduces other speakers) [syn: {master
        of ceremonies}, {emcee}]
     5: archaic terms for army [syn: {legion}]
     6: any organization that provides resources and facilities for
        a function or event; "Atlanta was chosen to be host for
        the Olympic Games"
     7: (medicine) recipient of transplanted tissue or organ from a
        donor
     8: the owner or manager of an inn [syn: {innkeeper}, {boniface}]
     9: a technical name for the bread used in the service of Mass
        or Holy Communion
     10: (computer science) a computer that provides client stations
         with access to files and printers as shared resources to
         a computer network [syn: {server}]
     v : be the host of or for; "We hosted 4 couples last night"

Source : Free On-Line Dictionary of Computing

host
     
        1.  A computer connected to a {network}.
     
        The term {node} includes devices such as routers and printers
        which would not normally be called "hosts".
     
        2.  A computer to which one connects using a
        {terminal emulator}.
     
        (1995-02-16)