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

deceleration \deceleration\ n.
   a decrease in velocity. opposite of acceleration

   syn: slowing, retardation.
        wordnet 1.5
see also:
acceleration 

[2] : WordNet (r) 2.0

deceleration
     n : a decrease in speed; "the deceleration of the arms race"
         syn: slowing, retardation ant: acceleration
see also:
slowing retardation acceleration 

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

71 moby thesaurus words for "deceleration":
   arrest, arrestation, catabasis, check, collapse, constraint,
   control, cooling, cooling down, cooling off, crash, curb,
   curtailment, declension, decline, decline and fall, decrescendo,
   delay, detention, diminuendo, dive, downtrend, downturn, drag,
   drop, dwindling, ease-off, ease-up, ebb, fall, flagging, hindrance,
   holdup, inhibition, injunction, interdict, lag, lapse,
   legal restraint, letdown, letup, minus acceleration, monopoly,
   obstruction, plunge, prohibition, protection, protectionism,
   protective tariff, rationing, rein, remission, restraint,
   restraint of trade, retardation, retardment, retreat, retrenchment,
   self-control, setback, slack-up, slackening, slowdown, slowing,
   slowing down, slowup, slump, subsidence, tariff wall,
   thought control, wane

Deceleration >> D Words
Deceleration, definition of term: Deceleration
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