las·civ·i·ous (l?-s?v??-?s)adj.1. Given to or expressing lust; lecherous.2. Exciting sexual desires; salacious.[Middle English, from Late Latin lasc?vi?sus, from Latin lasc?via, lewdness, playfulness, from lasc?vus, lustful, playful; see las- in Indo-European roots.]las·civ?i·ous·ly adv.las·civ?i·ous·ness n.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.lascivious (l??s?v??s) adj1. lustful; lecherous2. exciting sexual desire[C15: from Late Latin lasc?vi?sus, from Latin lasc?via wantonness, from lasc?vus] las?civiously adv las?civiousness nCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014las?civ?i?ous (l??s?v i ?s) adj. 1. inclined to lustfulness; wanton; lewd. 2. arousing sexual desire. 3. indicating sexual interest or expressive of lust or lewdness. [1400?50; late Middle English