Noun. 1. lower mantle-the deeper part of the mantle. layer-a relatively thin sheetlike expanse or region lying over or under another. mantle-the layer of the earth between the crust and the core.1  Facebook.. lower mantle-the deeper part of the mantle. layer-a relatively thin sheetlike expanse or region lying over or under another. mantle-the layer of the earth between the crust and the core.
Constitutional amendment. A constitutional amendment refers to the modification of the constitution of a nation or state. In many jurisdictions the text of the constitution itself is altered; in others the text is not changed, but the amendments change its effect. The method of modification is typically written into the constitution itself.
An amendment to the Constitution is an improvement, a correction or a revision to the original content approved in 1788. To date, 27 Amendments have been approved, six have been disapproved and thousands have been discussed.he other method of passing an amendment requires a Constitutional Convention to be called by two-thirds of the legislatures of the States. That Convention can propose as many amendments as it deems necessary. Those amendments must be approved by three-fourths of the states.