tax stamp n: a stamp affixed to an item as evidence that a tax on it has been paid
: one that the dealer of a controlled substance is required to purchase by payment of a tax according to a state law [an additional count of failure to purchase a tax stamp ]
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.