Password

Enchantment 
The reverse of the Name enchantment. A magical item with a Password functions unless the Password is spoken. If the Password is spoken, the item will be inert until the next time its powers would normally be invoked – or for one minute (choice of person making the item). An item may have some spells that are passworded and others that are not. The details, of course, depend on the spell.

Examples:

Energy cost to cast: 400. Halve this cost if the password is written on the item (must be readable). 
Prerequisite: Enchant.