Definitions
1.verbTo reduce the book value of (an asset) to zero.
2.verbTo record (an expenditure) as an expense.
3.verbTo remove a portion of a debt or an amount of an account owed, counting it as a loss (as a gesture of goodwill for example).
4.verbTo record a notional expense such as amortization or depreciation.
5.verbTo treat as a write-off, a total loss, especially something damaged beyond economic repair.
6.verbTo assign a low value to (something)."When Katya was injured, he wrote off the team's chances in the finals."