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

unrelenting \un`relent"ing\, a.
   not relenting; unyielding; rigid; hard; stern; cruel. --
   un`relent"ingly, adv. -- un`relent"ingness, n.
   1913 webster
see also:
un`relent"ingly un`relent"ingness 

[2] : WordNet (r) 2.0

unrelenting
     adj 1: not to be placated or appeased or moved by entreaty; "grim
            determination"; "grim necessity"; "russia's final
            hour, it seemed, approached with inexorable
            certainty"; "relentless persecution"; "the stern
            demands of parenthood" syn: grim, inexorable, relentless,
             stern, unappeasable, unforgiving
     2: never-ceasing; "the relentless beat of the drums" syn: persistent,
         relentless
see also:
grim inexorable relentless stern unappeasable unforgiving 
persistent 

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

137 moby thesaurus words for "unrelenting":
   adamant, adamantine, assiduous, cast-iron, constant, continuing,
   de longue haleine, diligent, dogged, dour, endless, enduring,
   extended, faithful, filled out, firm, flinty, fundamentalist, grim,
   hard, hard-core, hidebound, immovable, immutable, implacable,
   impliable, inalterable, indefatigable, indomitable, industrious,
   inelastic, inexorable, inflexible, insistent, intransigent,
   invincible, iron, ironbound, ironclad, ironhanded, irreconcilable,
   lasting, lengthy, long, long-drawn-out, long-spun, long-winded,
   longiloquent, loyal, merciless, mortal, muscle-bound, never-tiring,
   obdurate, obstinate, orthodox, padded, patient, patient as job,
   permanent, perseverant, persevering, persistent, persisting,
   pertinacious, plodding, plugging, preoccupied, procrustean, prolix,
   protracted, purist, puristic, puritan, puritanic, rapt, relentless,
   resolute, rigid, rigorist, rigoristic, rigorous, rock-ribbed,
   rockbound, ruthless, sedulous, single-minded, sleepless, slogging,
   spun-out, stable, steadfast, steady, steely, stern, stiff,
   straightlaced, straitlaced, stubborn, talkative, tenacious,
   tireless, unabating, unaffected, unalterable, unappeasable,
   unbending, unchangeable, uncompromising, unconquerable, undaunted,
   undiscouraged, undrooping, unfailing, unfaltering, unflagging,
   unflinching, ungiving, unintermitting, uninterrupted, unmoved,
   unnodding, unrelaxing, unremitting, unsleeping, unswerving,
   untiring, unwavering, unwearied, unwearying, unwinking, unyielding,
   utterly attentive, verbose, weariless, windy, wordy

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