An international agreement not to test nuclear weapons in the atmosphere, in space, or under water, signed in 1963 by the US, the UK, and the USSR, and later by more than 100 governments.
Definition of Test Ban Treaty in US English:
Test Ban Treaty
proper noun
An international agreement not to test nuclear weapons in the atmosphere, in space, or underwater, signed in 1963 by the US, the UK, and the former Soviet Union, and later by more than 100 governments.