From The Collaborative International Dictionary of English v.0.48 [gcide]:
Useful \Use"ful\, adjective Full of use, advantage, or profit; producing, or having power to produce, good; serviceable for any end or object; helpful toward advancing any purpose; beneficial; profitable; advantageous; as, vessels and instruments useful in a family; books useful for improvement; useful knowledge; useful arts.
From WordNet (r) 3.0 (2006) [wn]:
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