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

cop \cop\ ko^p, n. as. cop; cf. g. kopf head. cf. cup,
   cob.
   1. the top of a thing; the head; a crest. obs.
      1913 webster

            cop they used to call
            the tops of many hills.               --drayton.
      1913 webster

   2. a conical or conical-ended mass of coiled thread, yarn, or
      roving, wound upon a spindle, etc.
      1913 webster

   3. a tube or quill upon which silk is wound.
      1913 webster

   4. mil. arch. same as merlon.
      1913 webster

   5. a policeman. slang
      1913 webster

   cop waste, a kind of cotton waste, composed chiefly of
      remnants of cops from which the greater part of the yarn
      has been unwound.
      1913 webster copacetic
see also:
cup cob merlon cop waste 

[2] : WordNet (r) 2.0

cop
     n : uncomplimentary terms for a policeman syn: bull, copper,
          fuzz, pig
     v 1: take by theft; "someone snitched my wallet" syn: hook, snitch,
           thieve, knock off, glom
     2: take into custody; "the police nabbed the suspected
        criminals" syn: collar, nail, apprehend, arrest,
        pick up, nab
     also: copping, copped
see also:
bull copper fuzz pig hook snitch 
thieve knock off glom collar nail 
apprehend arrest pick up nab copping 
copped 

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

66 moby thesaurus words for "cop":
   dogberry, john law, abstract, and, annex, appropriate, bag,
   bluecoat, bobby, boost, borrow, bull, cabbage, clout, complex cone,
   cone, conelet, conoid, copper, cornet, crib, defraud, dick,
   embezzle, extort, filch, flatfoot, flattie, funnel, fuzz, gendarme,
   gumshoe, heat, hook, ice-cream cone, lift, make off with, man, nab,
   nip, officer, palm, peeler, pig, pilfer, pinch, pine cone, poach,
   purloin, run away with, rustle, scrounge, shamus, shoplift, snare,
   snatch, snitch, steal, swindle, swipe, take, the cops, the fuzz,
   the law, thieve, walk off with

[4] : Virtual Entity of Relevant Acronyms (Version 1.9, June 2002)

cop
     character-oriented protocol
     
     

C-Op >> C Words
C-Op, definition of term: C-Op
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