The Collaborative International Dictionary of English v.0.48:

Swell \Swell\, v. i. [imp. Swelled; p. p. Swelled or
   Swollen; p. pr. & vb. n. Swelling.] [AS. swellan; akin to
   D. zwellen, OS. & OHG. swellan, G. schwellen, Icel. svella,
   Sw. sv[aum]lla.]
   1. To grow larger; to dilate or extend the exterior surface
      or dimensions, by matter added within, or by expansion of
      the inclosed substance; as, the legs swell in dropsy; a
      bruised part swells; a bladder swells by inflation.
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   2. To increase in size or extent by any addition; to increase
      in volume or force; as, a river swells, and overflows its
      banks; sounds swell or diminish.
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   3. To rise or be driven into waves or billows; to heave; as,
      in tempest, the ocean swells into waves.
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   4. To be puffed up or bloated; as, to swell with pride.
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            You swell at the tartan, as the bull is said to do
            at scarlet.                           --Sir W.
                                                  Scott.
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   5. To be inflated; to belly; as, the sails swell.
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   6. To be turgid, bombastic, or extravagant; as, swelling
      words; a swelling style.
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   7. To protuberate; to bulge out; as, a cask swells in the
      middle.
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   8. To be elated; to rise arrogantly.
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            Your equal mind yet swells not into state. --Dryden.
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   9. To grow upon the view; to become larger; to expand.
      "Monarchs to behold the swelling scene!" --Shak.
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   10. To become larger in amount; as, many little debts added,
       swell to a great amount.
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   11. To act in a pompous, ostentatious, or arrogant manner; to
       strut; to look big.
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             Here he comes, swelling like a turkey cock. --Shak.
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The Collaborative International Dictionary of English v.0.48:

Swell \Swell\, a.
   Having the characteristics of a person of rank and
   importance; showy; dandified; distinguished; as, a swell
   person; a swell neighborhood. [Slang]
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   Swell mob. See under Mob. [Slang]
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The Collaborative International Dictionary of English v.0.48:

Swell \Swell\, n.
   1. The act of swelling.
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   2. Gradual increase. Specifically:
      (a) Increase or augmentation in bulk; protuberance.
      (b) Increase in height; elevation; rise.
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                Little River affords navigation during a swell
                to within three miles of the Miami. --Jefferson.
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      (c) Increase of force, intensity, or volume of sound.
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                Music arose with its voluptuous swell. --Byron.
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      (d) Increase of power in style, or of rhetorical force.
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                The swell and subsidence of his periods.
                                                  --Landor.
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   3. A gradual ascent, or rounded elevation, of land; as, an
      extensive plain abounding with little swells.
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   4. A wave, or billow; especially, a succession of large
      waves; the roll of the sea after a storm; as, a heavy
      swell sets into the harbor.
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            The swell
            Of the long waves that roll in yonder bay.
                                                  --Tennyson.
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            The gigantic swells and billows of the snow.
                                                  --Hawthorne.
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   5. (Mus.) A gradual increase and decrease of the volume of
      sound; the crescendo and diminuendo combined; -- generally
      indicated by the sign.
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   6. A showy, dashing person; a dandy. [Slang]
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   Ground swell. See under Ground.

   Organ swell (Mus.), a certain number of pipes inclosed in a
      box, the uncovering of which by means of a pedal produces
      increased sound.

   Swell shark (Zool.), a small shark (Scyllium ventricosum)
      of the west coast of North America, which takes in air
      when caught, and swells up like a swellfish.
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The Collaborative International Dictionary of English v.0.48:

Swell \Swell\, v. t.
   1. To increase the size, bulk, or dimensions of; to cause to
      rise, dilate, or increase; as, rains and dissolving snow
      swell the rivers in spring; immigration swells the
      population.
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            [The Church] swells her high, heart-cheering tone.
                                                  --Keble.
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   2. To aggravate; to heighten.
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            It is low ebb with his accuser when such
            peccadilloes are put to swell the charge.
                                                  --Atterbury.
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   3. To raise to arrogance; to puff up; to inflate; as, to be
      swelled with pride or haughtiness.
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   4. (Mus.) To augment gradually in force or loudness, as the
      sound of a note.
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WordNet (r) 3.0 (2006):

swell
    adj 1: very good; "he did a bully job"; "a neat sports car";
           "had a great time at the party"; "you look simply
           smashing" [syn: bang-up, bully, corking,
           cracking, dandy, great, groovy, keen, neat,
           nifty, not bad(p), peachy, slap-up, swell,
           smashing]
    n 1: the undulating movement of the surface of the open sea
         [syn: swell, crestless wave]
    2: a rounded elevation (especially one on an ocean floor)
    3: a crescendo followed by a decrescendo
    4: a man who is much concerned with his dress and appearance
       [syn: dandy, dude, fop, gallant, sheik, beau,
       swell, fashion plate, clotheshorse]
    v 1: increase in size, magnitude, number, or intensity; "The
         music swelled to a crescendo"
    2: become filled with pride, arrogance, or anger; "The mother
       was swelling with importance when she spoke of her son" [syn:
       swell, puff up]
    3: expand abnormally; "The bellies of the starving children are
       swelling" [syn: swell, swell up, intumesce, tumefy,
       tumesce]
    4: come up (as of feelings and thoughts, or other ephemeral
       things); "Strong emotions welled up"; "Smoke swelled from it"
       [syn: well up, swell]
    5: come up, as of a liquid; "Tears well in her eyes"; "the
       currents well up" [syn: well, swell]
    6: cause to become swollen; "The water swells the wood"