amendment
Changes in, or additions to, a constitution. Proposed by a two-thirds vote of both houses of Congress or by a convention called by Congress at the request of two-thirds of the state legislatures. Ratified by approval of three-fourths of the states.
An alteration proposed to a motion, a stage or clause of a bill, or to a committee report. It may attempt to present an improved formulation of the proposition under consideration or to provide an alternative to it.