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

perpetual \perpet"ual\, a. oe. perpetuel, f. perp'etuel,
   fr. l. perpetualis, fr. perpetuus continuing throughout,
   continuous, fr. perpes, -etis, lasting throughout.
   neverceasing; continuing forever or for an unlimited time;
   unfailing; everlasting; continuous.
   1913 webster

         unto the kingdom of perpetual night.     --shak.
   1913 webster

         perpetual feast of nectared sweets.      --milton.
   1913 webster

   circle of perpetual apparition, or circle of perpetual
   occultation. see under circle.

   perpetual calendar, a calendar so devised that it may be
      adjusted for any month or year.

   perpetual curacy ch. of eng., a curacy in which all the
      tithes are appropriated, and no vicarage is endowed.
      --blackstone.

   perpetual motion. see under motion.

   perpetual screw. see endless screw, under screw.
      1913 webster

   syn: continual; unceasing; endless; everlasting; incessant;
        constant; eternal. see constant.
        1913 webster
see also:
circle of perpetual apparition circle of perpetual occultation circle perpetual calendar perpetual curacy perpetual motion 
motion perpetual screw endless screw screw constant 

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

tax \tax\, n. f. taxe, fr. taxer to tax, l. taxare to touch,
   sharply, to feel, handle, to censure, value, estimate, fr.
   tangere, tactum, to touch. see tangent, and cf. task,
   taste.
   1. a charge, especially a pecuniary burden which is imposed
      by authority. specifically: 
      1913 webster
      a a charge or burden laid upon persons or property for
          the support of a government.
          1913 webster

                a farmer of taxes is, of all creditors,
                proverbially the most rapacious.  --macaulay.
          1913 webster
      b especially, the sum laid upon specific things, as upon
          polls, lands, houses, income, etc.; as, a land tax; a
          window tax; a tax on carriages, and the like.

   note: taxes are annual or perpetual, direct or
         indirect, etc.
         1913 webster
      c a sum imposed or levied upon the members of a society
          to defray its expenses.
          1913 webster

   2. a task exacted from one who is under control; a
      contribution or service, the rendering of which is imposed
      upon a subject.
      1913 webster

   3. a disagreeable or burdensome duty or charge; as, a heavy
      tax on time or health.
      1913 webster

   4. charge; censure. obs. --clarendon.
      1913 webster

   5. a lesson to be learned; a task. obs. --johnson.
      1913 webster

   tax cart, a spring cart subject to a low tax. eng.
      1913 webster

   syn: impost; tribute; contribution; duty; toll; rate;
        assessment; exaction; custom; demand.
        1913 webster
        1913 webster
see also:
tangent task taste annual perpetual direct 
indirect tax cart 

[3] : WordNet (r) 2.0

perpetual
     adj 1: continuing forever or indefinitely; "the ageless themes of
            love and revenge"; "eternal truths"; "life
            everlasting"; "hell's perpetual fires"; "the unending
            bliss of heaven" syn: ageless, eternal, everlasting,
             unending, unceasing
     2: uninterrupted in time and indefinitely long continuing; "the
        ceaseless thunder of surf"; "in constant pain"; "night and
        day we live with the incessant noise of the city"; "the
        never-ending search for happiness"; "the perpetual
        struggle to maintain standards in a democracy"; "man's
        unceasing warfare with drought and isolation";
        "unremitting demands of hunger" syn: ceaseless, constant,
         incessant, never-ending, unceasing, unremitting
     3: occurring so frequently as to seem ceaseless or
        uninterrupted; "a child's incessant questions"; "your
        perpetual or continual complaints" syn: incessant, endless
see also:
ageless eternal everlasting unending unceasing ceaseless 
constant incessant never-ending unremitting endless 

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

184 moby thesaurus words for "perpetual":
   abiding, age-long, aged, ageless, all-comprehensive, all-inclusive,
   all-knowing, all-powerful, all-seeing, all-wise, almighty, ancient,
   antique, boundless, ceaseless, changeless, chattering, chronic,
   coeternal, constant, continual, continuing, continuous, countless,
   creating, creative, dateless, diuturnal, durable, endless,
   enduring, eternal, eternally the same, eterne, ever-being,
   ever-durable, ever-during, evergreen, everlasting, everliving,
   exhaustless, extending everywhere, firm, fixed, frozen, glorious,
   good, hallowed, hardy, highest, holy, illimitable, illimited,
   immeasurable, immemorial, immense, immobile, immortal, immutable,
   incalculable, incessant, incomprehensible, indestructible,
   inexhaustible, infinite, infinitely continuous, innumerable,
   intact, interminable, interminate, intransient, invariable,
   inveterate, inviolate, just, lasting, limitless, long-lasting,
   long-lived, long-standing, long-term, longeval, longevous, loving,
   luminous, machine gun, macrobiotic, majestic, making, measureless,
   merciful, never-ceasing, never-ending, no end of, nonstop,
   nonterminating, nonterminous, numinous, of long duration,
   of long standing, olamic, omnipotent, omnipresent, omniscient, one,
   oscillating, perdurable, perduring, perennial, permanent,
   persistent, persisting, pulsating, quiescent, radiant, rapid,
   recurrent, regular, remaining, repeated, repetitive, rigid, sacred,
   sempervirent, sempiternal, shaping, shoreless, solid, sovereign,
   stable, staccato, static, stationary, staying, steadfast, steady,
   stuttering, sumless, supreme, sustained, termless, timeless,
   torpid, tough, ubiquitous, unaltered, unbounded, unbroken,
   unceasing, unchangeable, unchanged, unchanging, unchecked,
   uncircumscribed, undefined, undestroyed, undeviating, unending,
   unfading, unfailing, unfathomable, unintermitted, unintermittent,
   unintermitting, uninterrupted, universal, unlimited, unmeasurable,
   unmeasured, unnumbered, unplumbed, unremitting, unshifting,
   unstopped, untold, unvaried, unvarying, vibrating, vital,
   without bound, without end, without limit, without measure,
   without number

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

perpetual. that which is to last without limitation as to time; as, a 
perpetual statute, which is one without limit as to time, although not 
expressed to be so. 

Perpetual >> P Words
Perpetual, definition of term: Perpetual
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Perpetual Motio >> P Words
Perpetual Motio, definition of term: Perpetual Motio
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Perpetual Calen >> P Words
Perpetual Calen, definition of term: Perpetual Calen
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