"lockbox" is a correct and commonly used word in written English.
You can use it to refer to a secured box used to store items such as documents, jewelry, money, etc. Example sentence: I kept my valuable jewelry items in a lockbox for safekeeping.
He recommends setting up a "lockbox blog" that is hidden behind an internet firewall, but can be made visible to the public at short notice.
A pension or sovereign-wealth fund would earn a premium and in return deposit, say, $10 billion of treasuries in a lockbox.
In the late 1990s, America's Social Security surpluses were supposedly in a "lockbox"—which was prised open the moment the rest of the federal budget swung into deficit.
To avoid conflicts of interest, as Oracle's boss and the majority shareholder of a potential competitor, he has parked his shares in a "lockbox", a limited-liability company, so that he cannot intervene in NetSuite's day-to-day business.
And the marijuana is stashed high on a shelf in a lockbox.
He was the sort to let his sheep feed on the blighted tops of the heather and the wrack that blew up out of the sea, and he kept his heart closed up like a lockbox.
Mitch divulged where Doug hides the key to his lockbox of drugs, as he does in every iteration.
In Bill Clinton's last year in office, the federal government had a surplus of $236.4 billion, and the surplus was rhetorically dedicated, for all time, to a metaphoric "lockbox" devoted to the two biggest domestic federal programs, Social Security and Medicare.
On the left, attached to the door, is a lockbox.
The other provided the Wi-Fi password and an important message: "PLEASE KEEP KEYS IN THE LOCKBOX.
And on and on he went with the strong economy and the way he was gon' put Medicare in a lockbox where Congress couldn't mess with it.
