Done, given, or acting of one's own free will. (adjective)
Working or done without payment. (adjective)
A short piece of music, often having improvisation, played on a solo instrument (noun)
A volunteer (noun)
Examples of word voluntary
We also began to stress the word voluntary when we talked about the bill to make it clear that we were trying to help families, not substitute for them.
By the way, I doubt whether the term voluntary in relation to sexual selection ought to be employed: when a man is fascinated by a pretty girl it can hardly be called voluntary, and I suppose that female animals are charmed or excited in nearly the same manner by the gaudy males.
But we may go further, and inquire whether our volition, in what we term voluntary action, ever plays any other part than that of Descartes 'engineer, sitting in his office, and turning this tap or the other, as he wishes to set one or another machine in motion, but exercising no direct influence upon the movements of the whole.
IRS response: "The term voluntary compliance means that each of us is responsible for filing a tax return when required and for determining and paying the correct amount of tax."
The deal European leaders reached with banks will see some private holders of Greek debt accepting what they call a "voluntary" 50% reduction in the principal amounts they are owed.