[syn: ceaseless, constant, incessant, never-ending, perpetual, unceasing, unremitting]
The Collaborative International Dictionary of English v.0.48:
Unceasing \Unceasing\
   See ceasing.
WordNet (r) 3.0 (2006):
unceasing
    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, aeonian, eonian,
           eternal, everlasting, perpetual, 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, perpetual, unceasing, unremitting]
Moby Thesaurus II by Grady Ward, 1.0:
91 Moby Thesaurus words for "unceasing":
   abiding, ageless, articulated, catenated, ceaseless, chattering,
   coeternal, concatenated, connected, constant, continual, continued,
   continuing, continuous, cyclical, dateless, direct, endless,
   eternal, eterne, ever-being, ever-durable, ever-during,
   everlasting, everliving, featureless, gapless, immediate,
   immemorial, incessant, indefatigable, indestructible, infinite,
   interminable, joined, jointless, linked, machine gun, monotonous,
   never-ceasing, never-ending, nonstop, nonterminating, nonterminous,
   olamic, oscillating, perdurable, perennial, periodic, permanent,
   perpetual, persistent, pulsating, rapid, recurrent, regular,
   remaining, repeated, repetitive, round-the-clock, running,
   seamless, sempiternal, serried, smooth, stable, staccato, staying,
   steady, sticking, straight, stuttering, sustained, timeless,
   twenty-four-hour, unbroken, unchanging, undifferentiated, undying,
   unending, uniform, unintermitted, unintermittent, unintermitting,
   uninterrupted, unrelieved, unremitting, unstopped, unvarying,
   vibrating, without end