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

effectiveness \effect"iveness\, n.
   the quality of being effective.
   1913 webster

[2] : WordNet (r) 2.0

effectiveness
     n 1: power to be effective; the quality of being able to bring
          about an effect syn: effectivity, effectualness, effectuality
          ant: ineffectiveness
     2: capacity to produce strong physiological or chemical
        effects; "the toxin's potency"; "the strength of the
        drinks" syn: potency, strength
see also:
effectivity effectualness effectuality ineffectiveness potency strength 

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

139 moby thesaurus words for "effectiveness":
   acme, amperage, applicability, armipotence, authority,
   authorization, availability, be-all and end-all, beef, bite,
   bitingness, black power, blue ribbon, brute force, capability,
   championship, charge, charisma, clout, cogence, cogency, command,
   compulsion, control, cuttingness, dint, directorship, dominion,
   drive, duress, effect, effectuality, efficacy, efficiency, energy,
   first place, first prize, flower power, force, force majeure,
   forcefulness, full blast, full force, functionality, guts,
   headship, hegemony, height, helpfulness, highest, imperium,
   impressiveness, incisiveness, influence, jurisdiction, kingship,
   leadership, lordship, main force, main strength, mana, management,
   mastership, mastery, maximum, might, might and main, mightiness,
   mordancy, most, moxie, muscle power, ne plus ultra, nervosity,
   nervousness, new high, operability, palms, paramountcy,
   performance, pizzazz, poignancy, poop, potence, potency,
   potentiality, power, power pack, power structure, power struggle,
   powerfulness, practicability, practical utility, practicality,
   prepotency, presidency, primacy, productiveness, productivity,
   profitability, puissance, pull, punch, push, record, rule, say,
   serviceability, sinew, sinewiness, sovereignty, steam, strength,
   strong arm, strong language, superiority, superpower, supremacy,
   sway, top spot, trenchancy, usability, use, usefulness, utility,
   utilizability, validity, vehemence, verve, vigor, vigorousness,
   vim, virility, virtue, virulence, vitality, wattage, weight,
   zenith

Effectiveness >> E Words
Effectiveness, definition of term: Effectiveness
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