Definition of "unused"

If you have an unused credit for a year for which you also have additional tax liability because of an early disposal of an asset, you may reduce the added tax liability by the current year's unused credit that may be carried back solely because of recomputation of the investment credit for the prior year.

1972 October, “Losses from Operating a Farm”, in Farmer's Tax Guide: Income and Self Employment Tax (Internal Revenue Service; publication 225), Washington, D.C.: Internal Revenue Service, Department of the Treasury, published 1973, page 35

A particular problem is the disposal of small quantities of unwanted, surplus, or unused pesticides. Considerable attention has been given recently to the detoxification, prior to disposal, of sizable amounts of pesticides such as the herbicides returned from Vietnam. Some attention has also been given to the smaller amounts of unused pesticides at the consumer level, and in a few communities, specific pesticides such as DDT have been collected by authorities and safely disposed of by proven procedures.

1975 June, Edward W. Lawless, Thomas L. Ferguson, Alfred F. Meiners, “Introduction”, in Guidelines for the Disposal of Small Quantities of Unused Pesticides (Environmental Protection Technology Series; EPA-670/2-75-057), Cincinnati, Oh.: National Environmental Research Center, United States Environmental Protection Agency, page 9

The Lancaster House agreement's clauses on land distribution, which were later written into the independence constitution, are worth reading if only to understand why [Robert] Mugabe reserves some of his most vitriolic verbal assaults for the British who, as the one-time colonial power, presided over the conference. The clause made it extremely difficult for Zimbabwe's democratically elected government to procure land, even land that was unused. The legal hoops through which a government would have to jump to do so were designed to ensure that it would rarely, if ever, happen.

2001, George Alagiah, A Passage to Africa, London: Little, Brown Book Group

I pray you in your Letters, / When you ſhall theſe vnluckie deeds relate, / Speake of me, as I am. […] / Of one, whoſe ſubdu'd Eyes, / Albeit un-vsed to the melting moode, / Drops teares as faſt as the Arabian Trees / Their Medicinable gumme.

1603, William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies, London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, act V, scene ii, page 338

When I returned again to life, the same uproar, the same confused and violent movements, shook and deafened me; and presently, to my other pains and distresses, there was added the sickness of an unused landsman on the sea.

1886 May 1 – July 31, Robert Louis Stevenson, Kidnapped, being Memoirs of the Adventures of David Balfour in the Year 1751: […], London, Paris: Cassell & Company, published 1886

Oh shut up, Wally, Candy was thinking, although she understood why he couldn't stop babbling. He was unused to an environment he couldn't instantly brighten; he was unused to a place so despairing that it insisted on silence. He was unused to absorbing a shock, to simply taking it in. Wally's talk-a-mile style was a good-hearted effort; he believed in improving the world – he had to fix everything, to make everything better.

1985, John Irving, The Cider House Rules: A Novel, New York, N.Y.: William Morrow and Company, ISBN 978-0-688-03036-0; republished as The Cider House Rules, London: Black Swan, 1986, ISBN 978-0-552-99204-6, page 237

He [Nabokov] begins this first letter [to Véra Nabokov] with memorable abruptness and no salutation ('I won't hide it: I'm so unused to being—well, understood, perhaps—so unused to it, that in the very first minutes of our meeting I thought: this is a joke, a masquerade trick ... […]').

2014, Vladimir Nabokov, edited by Olga Voronina and Brian Boyd, Letters to Véra, London: Penguin Classics