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

usurpation \u`surpa"tion\, n. l. usurpatio ? making use,
   usurpation: cf. f. usurpation.
   1913 webster
   1. the act of usurping, or of seizing and enjoying; an
      authorized, arbitrary assumption and exercise of power,
      especially an infringing on the rights of others;
      specifically, the illegal seizure of sovereign power; --
      commonly used with of, also used with on or upon; as, the
      usurpation of a throne; the usurpation of the supreme
      power.
      1913 webster
      1913 webster

            he contrived their destruction, with the usurpation
            of the regal dignity upon him.        --sir t. more.
      1913 webster

            a law of a state which is a usurpation upon the
            general government.                   --o.
                                                  ellsworth.
      1913 webster

            manifest usurpation on the rights of other states.
                                                  --d. webster.
      1913 webster

   note: usurpation, in a peculiar sense, formerly denoted the
         absolute ouster and dispossession of the patron of a
         church, by a stranger presenting a clerk to a vacant
         benefice, who us thereupon admitted and instituted.
         1913 webster

   2. use; usage; custom. obs. --bp. pearson.
      1913 webster

[2] : WordNet (r) 2.0

usurpation
     n 1: entry to another's property without right or permission
          syn: trespass, encroachment, violation, intrusion
     2: wrongfully seizing and holding an office or powers by
        force especially the seizure of a throne or supreme
        authority; "a succession of generals who ruled by
        usurpation"
see also:
trespass encroachment violation intrusion 

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

43 moby thesaurus words for "usurpation":
   accession, adoption, anointing, anointment, appointment,
   appropriation, arrogation, assignment, assumption, authorization,
   colonization, conquest, consecration, coronation, delegation,
   deputation, election, empowerment, encroachment, enslavement,
   incursion, indent, infraction, infringement, inroad, intrusion,
   invasion, legitimate succession, occupation, overstepping,
   playing god, preemption, preoccupation, prepossession, requisition,
   seizure, subjugation, succession, takeover, taking over,
   transgression, trespass, trespassing

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

usurpation, torts. the unlawful assumption of the use of property which 
belongs to another; an interruption or the disturbing a man in his right and 
possession. toml. law dict. h.t. 
     2. according to lord coke, there are two kinds of usurpation. 1. when a 
stranger, without right, presents to a church, and his clerk is admitted; 
and, 2. when a subject uses a franchise of the king without lawful 
authority. co. litt. 277 b. 

[5] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

usurpation, government. the tyrannical assumption of the government by force 
contrary to and in violation of the constitution of the country. 

Usurpation >> U Words
Usurpation, definition of term: Usurpation
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