tax-deductible adjective Trending Now: More Trending: lowlife kakistocracy slimeball salacious oligarch SEE ALL See What's Trending Now See More Trending Words What's Trending Now More Trending Words lowlife 'a person of low moral character' kakistocracy 'government by the worst people' slimeball 'a morally repulsive or odious person' salacious 'arousing or appealing to sexual desire' oligarch 'government in which a small group exercises control' SEE ALL Time Traveler! Explore the year a word first appeared Definition of tax-deductible : allowed to be subtracted from the total amount of a person's income before calculating the tax he or she is required to pay : allowable as a deduction from taxes a tax-deductible donation Learn More about tax-deductible Nglish: Translation of tax-deductible for Spanish speakers Seen and Heard What made you want to look up tax-deductible? Please tell us where you read or heard it (including the quote, if possible). show hide