The US Congress can pass a law despite a President's veto by vote of a 2/3 majority in each House of the Congress.
This action is called an over-ride or over-riding of a veto.
The veto.
Veto
VETO
Congress can pass a BILL over the President's veto making it a law.
If a US president vetoes a bill sent to him by the US Congress, the president may choose to veto the bill. In such a case, the bill is sent back to the congress. If the Congress can come up with a two thirds majority, then the bill must pass as law.
when two thirds of each House of Congress agree to do so
Congress can override the Presidents veto by a Supermajority Vote (2/3 of members)
A president's veto can be overridden by Congress with a 2/3 majority in the House. If it is a pocket veto though, the veto cannot be overridden.
Using the veto indicates that the President disagrees with Congress and that Congress was willing to pass a law they against the President's wishes.
Congressional Override
Overriding a veto