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

harmless \harm"less\ haumrm"le^s, a.
   1. free from harm; unhurt; as, to give bond to save another
      harmless.
      1913 webster

   2. free from power or disposition to harm; innocent;
      inoffensive. " the harmless deer." --drayton

   syn: innocent; innoxious; innocuous; inoffensive;
        unoffending; unhurt; uninjured; unharmed.
        --harm"lessly, adv.- harm"lessness, n. harmonic
see also:
harm"lessly harm"lessness 

[2] : WordNet (r) 2.0

harmless
     adj 1: not causing or capable of causing harm; "harmless bacteria";
            "rendered the bomb harmless" ant: harmful
     2: not injurious to physical or mental health syn: innocuous
        ant: noxious
     3: not producing any toxic effects
     4: unlikely to harm or disturb anyone; "harmless old man" syn:
         innocuous
     5: not threatening to life or health; not malignant; "a benign
        tumor is usually harmless" syn: nonmalignant
see also:
harmful innocuous noxious nonmalignant 

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

67 moby thesaurus words for "harmless":
   benign, bright, dependable, fail-safe, firm, fresh, gentle,
   guaranteed, guiltless, innocent, innocuous, inoffensive, inviolate,
   invulnerable, mild, mint, nonmalignant, nonpoisonous, nontoxic,
   nonvirulent, painless, pristine, reliable, riskless, safe,
   scatheless, sound, stable, steady, trustworthy, unbroken,
   unbruised, undamaged, undamaging, undangerous, undefaced,
   undeformed, undemolished, undestroyed, unfaded, unharmed,
   unhazardous, unhurt, unhurtful, unimpaired, uninjured, uninjurious,
   unmaimed, unmangled, unmarked, unmarred, unobnoxious, unoffending,
   unperilous, unprecarious, unrisky, unscarred, unscathed,
   unscratched, unshattered, unspoiled, untorn, untouched, unwithered,
   unworn, virgin, warranteed

Harmless >> H Words
Harmless, definition of term: Harmless
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