From ACT Wiki
A cost necessarily incurred in performing duties as an employee or independent professional.
More generally, any cost necessarily incurred in order to do something.
3. Financial reporting - noun.
An item treated as a cost in the current reporting period, when preparing an income statement.
For example, a bad debt expense.
4. Financial reporting - verb.
To account for an item as an expense in the current reporting period, rather than capitalising it.
Capitalising an item of expenditure defers the accounting recognition of the expense into later reporting periods.