[1] : WordNet (r) 2.0

upgrade
     n 1: an upward slope or grade as in a road; "the car couldn't
          make it up the rise" syn: ascent, acclivity, rise,
           raise, climb ant: descent
     2: software that provides better performance than an earlier
        version did
     3: a reservation that is upgraded; "i got an upgrade to first
        class when coach class was full"
     4: the property possessed by a slope or surface that rises
        syn: rise, rising slope
     5: hardware that provides better performance than an earlier
        version did
     6: the act of improving something especially machinery by
        raising it to a higher grade as by adding or replacing
        components; "the power plant received a new upgrade"
     v 1: rate higher; raise in value or esteem ant: downgrade
     2: to improve, especially something that was old or outdated;
        "i've upgraded my computer so i can run better software";
        "the company upgraded their personnel"
     3: give a promotion to or assign to a higher position; "john
        was kicked upstairs when a replacement was hired"; "women
        tend not to advance in the major law firms"; "i got
        promoted after many years of hard work" syn: promote, advance,
         kick upstairs, raise, elevate ant: demote
     4: get better travel conditions; "i upgraded to first class
        when coach class was overbooked"
     5: give better travel conditions to; "the airline upgraded me
        when i arrived late and coach class was full"
see also:
ascent acclivity rise raise climb descent 
rising slope downgrade promote advance kick upstairs 
elevate demote 

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

145 moby thesaurus words for "upgrade":
   abruptness, acclinate, acclivitous, acclivity, acculturate,
   advance, aggrandize, ameliorate, amend, anabasis, anabatic,
   ascendant, ascending, ascension, ascensional, ascensive, ascent,
   aslant, aslantwise, aslope, at a slant, atilt, better, boost,
   breakthrough, bring forward, civilize, clamber, climb, climbing,
   downgrade, downhill, edify, educate, elevate, elevation, emend,
   enhance, enlighten, ennoble, enrich, escalade, exalt, fatten,
   favor, forward, foster, fountain, go straight, graduate, gush,
   gyring up, hike, improve, improve upon, in the ascendant, increase,
   jet, jump, kick upstairs, knight, lard, leap, leaping, levitation,
   lift, make an improvement, meliorate, mend, mount, mounting,
   nurture, off plumb, pass, precipitousness, prefer, promote, raise,
   rakingly, rampant, rearing, refine upon, reform, rise, rising,
   rising ground, rocketing up, saltation, saltatory, scandent,
   scansorial, shooting up, skyrocketing, slantingly, slantways,
   slantwise, slaunchways, slopeways, slopingly, soaring, socialize,
   spiraling, spout, spring, springing, spurt, steepness,
   straighten out, surge, takeoff, taking off, tipsily, transfigure,
   transform, up, uparching, upclimb, upcoming, updraft, upgang, upgo,
   upgoing, upgrowth, uphill, uphillward, upleap, uplift, upping,
   uprisal, uprise, uprising, uprush, upshoot, upslope, upsloping,
   upsurge, upsurgence, upsweep, upswing, upward, upwith, vault,
   verticalness, wax, zooming

[3] : The Free On-line Dictionary of Computing (27 SEP 03)

upgrade
     
        1. a new or better version of some hardware or software.
     
        often used in marketroid-speak to mean "bug fix".
     
        2. the act of developing or installing a new version.
     
        1995-03-14
     
     
see also:
hardware software marketroid bug fix 

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