constitutional amendment
A formal change to the Constitution's text. Twenty-seven have been ratified. An amendment outranks every statute, regulation, and prior court decision.
Amendments are how the document itself changes, as opposed to how it is reinterpreted. An amendment to a bill on the floor is an entirely different thing under the same word. The bar here is deliberately high: two-thirds of both chambers to propose, three-fourths of the states to ratify. That difficulty is why so much constitutional development happens through Supreme Court interpretation instead, and why an amendment, once ratified, is so hard to undo.
Also written as: amendment, amend the Constitution
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