WordNet (r) 3.0 (2006):
self-propelled adj 1: containing within itself the means of propulsion or movement; "a self-propelled vehicle" [syn: automotive, self-propelled, self-propelling] 2: moved forward by its own force or momentum; "a self-propelled egotist"; "the arms program is now self-propelled" [syn: self-propelled, self-propelling]