The Collaborative International Dictionary of English v.0.48:

Persistence \Per*sist"ence\, Persistency \Per*sist"en*cy\, n.
   [See Persistent.]
   1. The quality or state of being persistent; staying or
      continuing quality; hence, in an unfavorable sense,
      doggedness; obstinacy.
      [1913 Webster]

   2. The continuance of an effect after the cause which first
      gave rise to it is removed; as:
      (a) (Physics) The persistence of motion.
      (b) (Physiol.) Visual persistence, or persistence of the
          visual impression; auditory persistence, etc.
          [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

170 Moby Thesaurus words for "persistence":
   abidingness, accordance, adhesiveness, age, antiquity, application,
   assiduity, assiduousness, bulldog tenacity, bullheadedness, calm,
   changelessness, cohesiveness, commitment, concentration,
   consistency, consonance, constancy, continualness, continuance,
   continuation, continuity, correspondence, course, decidedness,
   decision, decisiveness, dedication, defeat of time,
   defiance of time, definiteness, demandingness, determinateness,
   determination, determinedness, devotion, diligence, diuturnity,
   dogged perseverance, doggedness, durability, durableness, duration,
   earnestness, endurance, engrossment, equability, equanimity,
   equilibrium, evenness, exigency, extension, fidelity, firmness,
   fixedness, frozenness, gluiness, glutinosity, grit, gumminess,
   hardening, homogeneity, immobility, immovability, immovableness,
   immutability, importunacy, importunateness, importunity,
   indefatigability, industriousness, industry, insistence,
   insistency, invariability, invariableness, inveteracy, lastingness,
   lengthening, long standing, long-lastingness, long-livedness,
   longevity, loyalty, maintenance, monolithism, obduracy, obstinacy,
   patience, patience of Job, perdurability, perennation, permanence,
   permanency, perpetualness, perpetuation, perpetuity, perseverance,
   persistency, pertinaciousness, pertinacity, plodding, pluck,
   plugging, preoccupation, pressingness, pressure, progress,
   progression, prolongation, protraction, purpose, purposefulness,
   pursuance, quiescence, relentlessness, repetition, resoluteness,
   resolution, resolve, resolvedness, retention, rigidity, run,
   sedulity, sedulousness, self-will, seriousness, sincerity,
   single-mindedness, singleness of purpose, slogging, snugness,
   solidity, stability, stamina, standing, stasis, staying power,
   steadfastness, steadiness, stick-to-itiveness, stickiness,
   straight course, stubbornness, survival, survivance,
   sustained action, sustenance, tackiness, tenaciousness, tenacity,
   tightness, tirelessness, torpor, total commitment, toughness,
   unchangeability, unchangingness, uniformity, uninterrupted course,
   unity, unremittingness, unruffledness, unswerving attention,
   urgency, viscidity, viscosity, way, will