Source : Webster's Revised Unabridged Dictionary (1913)

Upon \Up*on"\, prep.[AS. uppan, uppon; upp up + on, an, on. See
   {Up}, and {On}.]
   On; -- used in all the senses of that word, with which it is
   interchangeable. ``Upon an hill of flowers.'' --Chaucer.

         Our host upon his stirrups stood anon.   --Chaucer.

         Thou shalt take of the blood that is upon the altar.
                                                  --Ex. xxix.
                                                  21.

         The Philistines be upon thee, Samson.    --Judg. xvi.
                                                  9.

         As I did stand my watch upon the hill.   --Shak.

         He made a great difference between people that did
         rebel upon wantonness, and them that did rebel upon
         want.                                    --Bacon.

         This advantage we lost upon the invention of firearms.
                                                  --Addison.

         Upon the whole, it will be necessary to avoid that
         perpetual repetition of the same epithets which we find
         in Homer.                                --Pope.

         He had abandoned the frontiers, retiring upon Glasgow.
                                                  --Sir. W.
                                                  Scott.

         Philip swore upon the Evangelists to abstain from
         aggression in my absence.                --Landor.

   Note: Upon conveys a more distinct notion that on carries
         with it of something that literally or metaphorically
         bears or supports. It is less employed than it used to
         be, on having for the most part taken its place. Some
         expressions formed with it belong only to old style;
         as, upon pity they were taken away; that is, in
         consequence of pity: upon the rate of thirty thousand;
         that is, amounting to the rate: to die upon the hand;
         that is, by means of the hand: he had a garment upon;
         that is, upon himself: the time is coming fast upon;
         that is, upon the present time. By the omission of its
         object, upon acquires an adverbial sense, as in the
         last two examples.

   {To assure upon} (Law), to promise; to undertake.

   {To come upon}. See under {Come}.

   {To take upon}, to assume.



   {To come to time}.
      (a) (Prize Fighting) To come forward in order to resume
          the contest when the interval allowed for rest is over
          and ``time'' is called; hence:
      (b) To keep an appointment; to meet expectations.
          [Colloq.]

   {To come together}.
      (a) To meet for business, worship, etc.; to assemble.
          --Acts i. 6.
      (b) To live together as man and wife. --Matt. i. 18.

   {To come true}, to happen as predicted or expected.

   {To come under}, to belong to, as an individual to a class.
      

   {To come up}
      (a) to ascend; to rise.
      (b) To be brought up; to arise, as a question.
      (c) To spring; to shoot or rise above the earth, as a
          plant.
      (d) To come into use, as a fashion.

   {To come up the capstan} (Naut.), to turn it the contrary
      way, so as to slacken the rope about it.

   {To come up the tackle fall} (Naut.), to slacken the tackle
      gently. --Totten.

   {To come up to}, to rise to; to equal.

   {To come up with}, to overtake or reach by pursuit.

   {To come upon}.
      (a) To befall.
      (b) To attack or invade.
      (c) To have a claim upon; to become dependent upon for
          support; as, to come upon the town.
      (d) To light or chance upon; to find; as, to come upon hid
          treasure.