ninjutsu (n?n?d??tsu?; n?n?d??tsu?) n (Martial Arts (other than Judo & Karate) & Combat Sports) a Japanese martial art practised for espionage purposes, using camouflage and stealthy movementsCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014