write down1. To set down in writing.2. Accounting To record a reduced value for (an asset): forced to write down a security after a fall in its market value.3. Accounting To record (a loss) by reducing the value of an asset: wrote down $10 million in bad debt.4. To write in a conspicuously simple or condescending style: felt he had to write down to his students.5. To disparage in writing: a film that was written down in the magazine.write in1. To cast a vote by inserting (a name not listed on a ballot).2. To insert in a text or document: wrote in an apology at the end of the note.3. To communicate with an organization by mail: write in with a completed entry form.write off1. Accounting To record (a worthless asset) as a loss.2. Accounting To record (a loss or expense) as a reduction in earnings or in the value of an asset: wrote off business expenses when calculating taxable income.3. To consider as a loss or failure: wrote off the rainy first day of the vacation.4. To disregard as inconsequential: wrote off the singer as a novelty act.write out1. To express or compose in writing: write out a request.2. To write in full or expanded form: All abbreviations are to be written out.write up1. To write a report or description of, as for publication.2. Accounting To record an increased value for (an asset).3. To report (someone) in writing, as for breaking the law: wrote him up for speeding.4. To bring (a journal, for example) up to date.