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

compulsory \compul"sory\, a. ll. compulsorius.
   1. having the power of compulsion; constraining.
      1913 webster

   2. obligatory; enjoined by authority; necessary; due to
      compulsion.
      1913 webster

            this contribution threatening to fall infinitely
            short of their hopes, they soon made it compulsory.
                                                  --burke.
      1913 webster

[2] : WordNet (r) 2.0

compulsory
     adj : required by rule; "in most schools physical education are
           compulsory"; "attendance is mandatory"; "required
           reading" syn: mandatory, required
see also:
mandatory required 

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

41 moby thesaurus words for "compulsory":
   absolute, binding, choiceless, coactive, compelling, compulsatory,
   compulsive, conclusive, constraining, decisive, decretory,
   dictated, driving, entailed, exigent, final, hard-and-fast,
   imperative, imperious, importunate, imposed, inevitable,
   involuntary, irresistible, irrevocable, mandated, mandatory, must,
   necessary, necessitous, obligatory, peremptory, prescript,
   prescriptive, pressing, required, restraining, ultimate, urgent,
   without appeal, without choice

Compulsory >> C Words
Compulsory, definition of term: Compulsory
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