useful Definition

useful
adj

1. Able to be used advantageously; serving a helpful purpose; able to be put to various purposes.

Thesaurus: handy, helpful, serviceable, advantageous, practical, valuable, productive, beneficial, effective, worthwhile, convenient, fruitful; Antonym: inefficient.
2. colloq
Skilled or proficient.
Example: Booth put in a useful performance for Aberdeen

Derivative: usefully
adverb

Derivative: usefulness
noun

Idiom: come in useful

To prove to be useful.

Etymology: 16c.