usefulness

n. state of being beneficial, condition of being useful

In economics, utility is a measure of the relative satisfaction or desiredness from consumption of goods. Given this measure, one may speak meaningfully of increasing or decreasing utility, and thereby explain economic behavior in terms of attempts to increase one's utility. A theoretical unit of measurement for utility is the 'util'.
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Noun
1. the quality of being of practical use
(synonym) utility
(antonym) inutility, uselessness, unusefulness
(hypernym) quality
(hyponym) detergency, detergence
(attribute) useful, utile

(n.)
The quality or state of being useful; utility; serviceableness; advantage.
  

Synonyms and related words:
account, advantage, advantageousness, advisability, agreeableness, applicability, appropriateness, auspiciousness, availability, beneficialness, benefit, benevolence, benignity, class, cogency, convenience, decency, desert, desirability, effectiveness, efficacy, efficiency, excellence, expedience, expediency, fairness, favorableness, feasibility, fineness, first-rateness, fitness, fittingness, fruitfulness, functionality, gain, goodliness, goodness, grace, healthiness, help, helpfulness, kindness, merit, niceness, operability, opportuneness, percentage, pleasantness, point, politicness, practicability, practical utility, practicality, profit, profitability, profitableness, propriety, prudence, purpose, purposefulness, quality, relevance, rewardingness, rightness, seasonableness, seemliness, service, serviceability, skillfulness, soundness, suitability, superiority, timeliness, usability, use, utility, utilizability, validity, value, virtue, virtuousness, wholeness, wisdom, worth, worthwhileness