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

punish \pun"ish\, v. t. imp.  p. p. punished; p. pr.  vb.
   n. punishing. oe. punischen, f. punir, from l. punire,
   punitum, akin to poena punishment, penalty. see pain, and
   -ish.
   1. to impose a penalty upon; to afflict with pain, loss, or
      suffering for a crime or fault, either with or without a
      view to the offender's amendment; to cause to suffer in
      retribution; to chasten; as, to punish traitors with
      death; a father punishes his child for willful
      disobedience.
      1913 webster

            a greater power
            now ruled him, punished in the shape he sinned.
                                                  --milton.
      1913 webster

   2. to inflict a penalty for an offense upon the offender;
      to repay, as a fault, crime, etc., with pain or loss; as,
      to punish murder or treason with death.
      1913 webster

   3. to injure, as by beating; to pommel. low
      1913 webster

   4. to deal with roughly or harshly; -- chiefly used with
      regard to a contest; as, our troops punished the enemy.
      colloq. or slang
      webster 1913 suppl.

   syn: to chastise; castigate; scourge; whip; lash; correct;
        discipline. see chasten.
        1913 webster
see also:
punished punishing pain -ish chasten 

[2] : WordNet (r) 2.0

punishing
     adj 1: resulting in punishment; "the king imposed a punishing tax"
     2: characterized by toilsome effort to the point of exhaustion;
        especially physical effort; "worked their arduous way up
        the mining valley"; "a grueling campaign"; "hard labor";
        "heavy work"; "heavy going"; "spent many laborious hours
        on the project"; "set a punishing pace" syn: arduous, backbreaking,
         grueling, gruelling, hard, heavy, laborious, toilsome
see also:
arduous backbreaking grueling gruelling hard heavy 
laborious toilsome 

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

53 moby thesaurus words for "punishing":
   herculean, arduous, backbreaking, burdensome, castigatory,
   chastening, chastising, corrective, crushing, demanding,
   disciplinary, draining, effortful, exhausting, fatiguesome,
   fatiguing, forced, grueling, hard, hard-earned, hard-fought, heavy,
   hefty, inflictive, killing, labored, laborious, onerous, operose,
   oppressive, painful, penal, penological, punitive, punitory,
   retributive, strained, straining, strenuous, stressful, taxing,
   tiresome, tiring, toilsome, torturous, tough, troublesome, trying,
   uphill, weariful, wearing, wearisome, wearying

Punishing >> P Words
Punishing, definition of term: Punishing
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