deductible [dɪˈdʌktəbəɫ]adjective 1noun 1forms 3 adjective1 •Eligible to be deducted.(Normally forgiven debt is taxable and only business expenses paid for with company income are deductible.) — 2021 noun1 •(US) An amount of expenses that must be paid out of pocket before an insurer will pay further expenses. formsdeductibles · more deductible · most deductible