FLATTEN

[flat.ten] vb flat.tened ; flat.ten.ing vt (1630): to make flat: as a: to make level or smooth b: to knock down; also: to defeat decisively c: to make dull or uninspired--often used with out d: to make (as paint) lusterless e: to stabilize esp. at a lower level ~ vi: to become flat or flatter: as a: to become dull or spiritless b: to extend in or into a flat position or form c: to become uniform or stabilized often at a new lower level--usu. used with out -- flat.ten.er n