Gross interest
From ACT Wiki
1.
Tax.
Interest stated before offsetting tax effects, if any.
In this sense, gross interest receivable means interest receivable stated before deducting any tax payable thereon.
In this context, gross interest payable means interest payable stated before offsetting any tax relief enjoyed on the interest expense.
2.
Interest (usually) payable, stated before deducting other interest (usually) receivable in the same period.