1. To deduct or subtract from a cost or the price of something.
2. To purchase or to sell (a bill, note, or other commercial paper) at a reduction equal to the amount of interest that will accumulate before it matures.
3. To lend money on (a commercial paper not immediately payable) after deducting the interest.
4. To sell or offer something for sale at a reduced price.
5. To reduce in quantity or value.
6. To underestimate the significance or effectiveness of something or someone; to minimize: "Her husband took care not to discount his wife's accomplishments."
7. To regard with doubt or disbelief.