Source : Webster's Revised Unabridged Dictionary (1913)

Mass \Mass\, v. i. [imp. & p. p. {Massed}; p. pr. & vb. n.
   {Massing}.]
   To celebrate Mass. [Obs.] --Hooker.

Mass \Mass\, n. [OE. masse, F. masse, L. massa; akin to Gr. ? a
   barley cake, fr. ? to knead. Cf. {Macerate}.]
   1. A quantity of matter cohering together so as to make one
      body, or an aggregation of particles or things which
      collectively make one body or quantity, usually of
      considerable size; as, a mass of ore, metal, sand, or
      water.

            If it were not for these principles, the bodies of
            the earth, planets, comets, sun, and all things in
            them, would grow cold and freeze, and become
            inactive masses.                      --Sir I.
                                                  Newton.

            A deep mass of continual sea is slower stirred To
            rage.                                 --Savile.

   2. (Phar.) A medicinal substance made into a cohesive,
      homogeneous lump, of consistency suitable for making
      pills; as, blue mass.

   3. A large quantity; a sum.

            All the mass of gold that comes into Spain. --Sir W.
                                                  Raleigh.

            He had spent a huge mass of treasure. --Sir J.
                                                  Davies.

   4. Bulk; magnitude; body; size.

            This army of such mass and charge.    --Shak.

   5. The principal part; the main body.

            Night closed upon the pursuit, and aided the mass of
            the fugitives in their escape.        --Jowett
                                                  (Thucyd.).

   6. (Physics) The quantity of matter which a body contains,
      irrespective of its bulk or volume.

   Note: Mass and weight are often used, in a general way, as
         interchangeable terms, since the weight of a body is
         proportional to its mass (under the same or equal
         gravitative forces), and the mass is usually
         ascertained from the weight. Yet the two ideas, mass
         and weight, are quite distinct. Mass is the quantity of
         matter in a body; weight is the comparative force with
         which it tends towards the center of the earth. A mass
         of sugar and a mass of lead are assumed to be equal
         when they show an equal weight by balancing each other
         in the scales.

   {Blue mass}. See under {Blue}.

   {Mass center} (Geom.), the center of gravity of a triangle.
      

   {Mass copper}, native copper in a large mass.

   {Mass meeting}, a large or general assembly of people,
      usually a meeting having some relation to politics.

   {The masses}, the great body of the people, as contrasted
      with the higher classes; the populace.

Mass \Mass\, n. [OE. masse, messe, AS. m[ae]sse. LL. missa, from
   L. mittere, missum, to send, dismiss: cf. F. messe. In the
   ancient churches, the public services at which the
   catechumens were permitted to be present were called missa
   catechumenorum, ending with the reading of the Gospel. Then
   they were dismissed with these words : ``Ite, missa est''
   [sc. ecclesia], the congregation is dismissed. After that the
   sacrifice proper began. At its close the same words were said
   to those who remained. So the word gave the name of Mass to
   the sacrifice in the Catholic Church. See {Missile}, and cf.
   {Christmas}, {Lammas}, {Mess} a dish, {Missal}.]
   1. (R. C. Ch.) The sacrifice in the sacrament of the
      Eucharist, or the consecration and oblation of the host.

   2. (Mus.) The portions of the Mass usually set to music,
      considered as a musical composition; -- namely, the Kyrie,
      the Gloria, the Credo, the Sanctus, and the Agnus Dei,
      besides sometimes an Offertory and the Benedictus.

   {Canon of the Mass}. See {Canon}.

   {High Mass}, Mass with incense, music, the assistance of a
      deacon, subdeacon, etc.

   {Low Mass}, Mass which is said by the priest through-out,
      without music.

   {Mass bell}, the sanctus bell. See {Sanctus}.

   {Mass book}, the missal or Roman Catholic service book.

Mass \Mass\, v. t.
   To form or collect into a mass; to form into a collective
   body; to bring together into masses; to assemble.

         But mass them together and they are terrible indeed.
                                                  --Coleridge.

Source : WordNet®

mass
     adj 1: occurring widely (as to many people); "mass destruction"
            [syn: {large-scale}]
     2: gathered or tending to gather into a mass or whole;
        "aggregate expenses include expenses of all divisions
        combined for the entire year"; "the aggregated amount of
        indebtedness" [syn: {aggregate}, {aggregated}, {aggregative}]
     [also: {masses} (pl)]

mass
     n 1: the property of a body that causes it to have weight in a
          gravitational field
     2: (often followed by `of') a large number or amount or extent;
        "a batch of letters"; "a deal of trouble"; "a lot of
        money"; "he made a mint on the stock market"; "it must
        have cost plenty" [syn: {batch}, {deal}, {flock}, {good
        deal}, {great deal}, {hatful}, {heap}, {lot}, {mess}, {mickle},
         {mint}, {muckle}, {peck}, {pile}, {plenty}, {pot}, {quite
        a little}, {raft}, {sight}, {slew}, {spate}, {stack}, {tidy
        sum}, {wad}, {whole lot}, {whole slew}]
     3: an ill-structured collection of similar things (objects or
        people)
     4: (Roman Catholic Church and Protestant Churches) the
        celebration of the Eucharist
     5: a body of matter without definite shape; "a huge ice mass"
     6: the common people generally; "separate the warriors from the
        mass"; "power to the people" [syn: {multitude}, {masses},
        {hoi polloi}, {people}]
     7: the property of something that is great in magnitude; "it is
        cheaper to buy it in bulk"; "he received a mass of
        correspondence"; "the volume of exports" [syn: {bulk}, {volume}]
     8: a musical setting for a Mass; "they played a Mass composed
        by Beethoven"
     9: a sequence of prayers constituting the Christian eucharistic
        rite; "the priest said Mass"
     [also: {masses} (pl)]

mass
     v : join together into a mass or collect or form a mass; "Crowds
         were massing outside the palace"
     [also: {masses} (pl)]