early 15c., "action of deducting," from Middle French déduction or directly from Latin deductionem (nominative deductio), noun of action from past participle stem of deducere (see deduce). Meaning "that which is deducted" is from 1540s. As a term in logic, from Late Latin use of deductio as a loan-translation of Greek apagoge.
1. The allowable deduction is apportioned between the estate and the beneficiaries.
2. It was a pretty astute deduction.
3. He arrived at the solution by a simple process of deduction.
4. No deduction in pay is made for absence due to illness.