[1] : The Collaborative International Dictionary of English v.0.48

overweight \o"verweight`\, n.
   1. weight over and above what is required by law or custom.
      1913 webster

   2. superabundance of weight; preponderance.
      1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

overweight \o"verweight"\, a.
   1. overweighing; excessive. obs. "of no overweight worth."
      --fuller.
      1913 webster

   2. having a weight in excess of what is normal, proper, or
      expected; as, the doctor recommends dieting to all his
      overweight patients; overweight luggage will incur an
      extra charge.
      pjc

[3] : WordNet (r) 2.0

overweight
     adj : usually describes a large person who is fat but has a large
           frame to carry it syn: fleshy, heavy
     n : the property of excessive fatness syn: corpulence, stoutness,
          adiposis
see also:
fleshy heavy corpulence stoutness adiposis 

[4] : Moby Thesaurus II by Grady Ward, 1.0

158 moby thesaurus words for "overweight":
   adipose, avoirdupois, bear hard upon, beef, beefiness, beefy,
   big-bellied, bloated, blowzy, bosomy, brawny, burden, burly,
   burthen, buxom, charge, choke, chubby, chunky, congest, congestion,
   corpulent, cram, crowd, cumber, deadweight, distended, drench,
   dumpy, encumber, engorgement, fat, fatness, fattish, fleshy,
   freight, full, giantism, gigantism, glut, gluttonize, gorge,
   gravity, gross, gross weight, hamper, handicap, heaviness, heavy,
   heavyset, heavyweight, heft, heftiness, hefty, hippy, hyperemia,
   hypertrophy, imposing, jam, jam-pack, lade, leaden, liveweight,
   load, lusty, massive, massy, meaty, neat weight, net, net weight,
   obese, oppress, outbalance, outpoise, outsize, outsized, outweigh,
   overbalance, overbig, overbrimming, overburden, overcharge,
   overdeveloped, overdevelopment, overfed, overfeed, overfill,
   overflow, overfreight, overfullness, overgrown, overgrowth,
   overlade, overlarge, overlargeness, overload, overpoise, oversized,
   overspill, overstuff, overtax, overweigh, pack, paunchy, plethora,
   plump, podgy, ponderability, ponderosity, ponderous, ponderousness,
   portly, potbellied, poundage, press hard upon, pudgy, puffy, pursy,
   repletion, rest hard upon, roly-poly, rotund, saddle, satiate,
   satiety, saturate, saturation, soak, square, squat, squatty,
   stalwart, stocky, stout, strapping, stuff, supercharge,
   supersaturate, supersaturation, surcharge, surfeit, swollen, tax,
   thick-bodied, thickset, tonnage, too big, top-heavy, tubby,
   underweight, weigh heavy on, weigh on, weigh upon, weight,
   weightiness, weighty, well-fed

Overweight >> O Words
Overweight, definition of term: Overweight
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