thorn moth
n (Animals) any of various woodland geometrid moths, typified by the large thorn (Ennomos autumnaria), having wings set somewhat at an angle and held up when at rest. Often shortened to: thorn
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014