Having a beneficial use; serviceable: a useful kitchen gadget. (adjective)
Being of practical use: a useful job; useful members of society. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "useful" in a sentence
"In this workshop, children are invited to make educational and useful toys - useful in the sense that they help with a childs early development, providing stimulation, exercise, use of the senses, and learning of skills."
"Let a child be employed -- take an interest in his employment, let him fancy that he is useful -- _and he is useful_, he is laying in a stock of health."
"Exactly the same difficulty arises, when we endeavour to account for the development of the moral sense or conscience in savage man; for although the _practice_ of benevolence, honesty, or truth, may have been useful to the tribe possessing these virtues, that does not at all account for the peculiar _sanctity_, attached to actions which each tribe considers right and moral, as contrasted with the very different feelings with which they regard what is merely _useful_."