funds that are not declared in an organization's accounting books; also called secret reserve
capabilities beyond those normally available to someone
something kept in reserve and concealed, esp. not declared on a balance sheet or account
She has a hidden reserve of candy bars.
He and a picket were cut off from the main body by a hidden reserve of the enemy.
She always felt sure that there was some hidden reserve of rebellion in Jerome, coerce him into obedience as she might.
But even as he exulted, Buck drew upon some hidden reserve of strength and pulled up even again.