1. [n]  a structure taller than its diameter; can stand alone or be attached to a larger building
2. [n]  a powerful small boat designed to pull or push larger ships
3. [n]  anything tall and thin approximating the shape of a column or tower; "the test tube held a column of white powder"; "a tower of dust rose above the horizon"; "a thin pillar of smoke betrayed their campsite"
4. [v]  appear very large or occupy a commanding position; "The huge sculpture predominates over the fountain"; "Large shadows loomed on the canyon wall"

Tower
The author of this memoir combines his account of building a purely decorative tower to adorn a plot of land in Maine with speculations on the towers that loom large in the world`s imaginative history, including the Tower of Babel, the Eiffel Tower, and the Martello tower in Joyce`s ULYSSES.

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1. \Tow"er\, n. [OE. tour,tor,tur, F. tour, L. turris; akin
   to Gr. ?; cf. W. twr a tower, Ir. tor a castle, Gael. torr a
   tower, castle. Cf. {Tor}, {Turret}.]
   1. (Arch.)
      (a) A mass of building standing alone and insulated,
          usually higher than its diameter, but when of great
          size not always of that proportion.
      (b) A projection from a line of wall, as a fortification,
          for purposes of defense, as a flanker, either or the
          same height as the curtain wall or higher.
      (c) A structure appended to a larger edifice for a special
          purpose, as for a belfry, and then usually high in
          proportion to its width and to the height of the rest
          of the edifice; as, a church tower.
   2. A citadel; a fortress; hence, a defense.
            Thou hast been a shelter for me, and a strong tower
            from the enemy.                       --Ps. lxi. 3.
   3. A headdress of a high or towerlike form, fashionable about
      the end of the seventeenth century and until 1715; also,
      any high headdress.
            Lay trains of amorous intrigues In towers, and
            curls, and periwigs.                  --Hudibras.
   4. High flight; elevation. [Obs.] --Johnson.
   {Gay Lussac's tower} (Chem.), a large tower or chamber used
      in the sulphuric acid process, to absorb (by means of
      concentrated acid) the spent nitrous fumes that they may
      be returned to the Glover's tower to be reemployed. See
      {Sulphuric acid}, under {Sulphuric}, and {Glover's tower},
      below.
   {Glover's tower} (Chem.), a large tower or chamber used in
      the manufacture of sulphuric acid, to condense the crude
      acid and to deliver concentrated acid charged with nitrous
      fumes. These fumes, as a catalytic, effect the conversion
      of sulphurous to sulphuric acid. See {Sulphuric acid},
      under {Sulphuric}, and {Gay Lussac's tower}, above.
   {Round tower}. See under {Round}, a.
   {Shot tower}. See under {Shot}.
   {Tower bastion} (Fort.), a bastion of masonry, often with
      chambers beneath, built at an angle of the interior
      polygon of some works.
   {Tower mustard} (Bot.), the cruciferous plant {Arabis
      perfoliata}.
   {Tower of London}, a collection of buildings in the eastern
      part of London, formerly containing a state prison, and
      now used as an arsenal and repository of various objects
      of public interest.
   

2. \Tow"er\, v. i. [imp. & p. p. {towered}; p. pr. & vb. n.
   {towering}.]
   To rise and overtop other objects; to be lofty or very high;
   hence, to soar.
         On the other side an high rock towered still.
                                                  --Spenser.
         My lord protector's hawks do tower so well. --Shak.
   

3. \Tow"er\, v. t.
   To soar into. [Obs.] --Milton.